Develop Reference

Surface View and Linear layout and onClick event

I have a problem with adding my surface view to a linear layout, I have tried the already available answers and still cant seem to figure it out. My aim is to render an animation at the bottom of my login screen when my the next button is clicked. I tried adding a linear Layout to the Screen and then adding my gameView object on to that.
This is the loginActivity and game View Class for clarity I've also added the xml.
`package com.example.Combat;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.*;
import android.os.Bundle;
import android.util.Log;
import android.view.*;
import android.widget.LinearLayout;
import android.widget.TextView;
public class MyActivity extends Activity {
/**
* Called when the activity is first created.
*/
public GameView gameView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//setting the font
Typeface myTypeFace = Typeface.createFromAsset(getAssets(),"Typo Oxin free promo.ttf");
TextView myTextView = (TextView) findViewById(R.id.nameTextView);
myTextView.setTypeface(myTypeFace);
gameView = new GameView(this);
// LinearLayout.LayoutParams lp =new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
// lp.gravity= Gravity.BOTTOM;
LinearLayout myLayout = new LinearLayout(this);
myLayout.findViewById(R.id.gameLayoutView);
myLayout.addView(gameView);
}
#Override
public void onResume(){
super.onResume();
gameView.resume();
}
#Override
protected void onPause(){
super.onPause();
gameView.pause();
}
public void beginMotion(View view) {
GameView.isMoving=!GameView.isMoving;
// startActivity(new Intent(getApplicationContext(),transitionActivity.class));
}
}
`
package com.example.Combat;
import android.content.Context;
import android.graphics.*;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
/**
* Created by vmuser on 2017/05/05.
*/
public class GameView extends SurfaceView implements Runnable{
private Thread gameThread;
private SurfaceHolder ourHolder;
public static volatile boolean playing=false;
private Canvas canvas;
private Bitmap bitmapRunningMan;
public static boolean isMoving=false;
private float runSpeedPerSecond = 150;
//LinearLayout screen=(LinearLayout)findViewById(R.id.theScreen);
private float manXPos = 1020, manYPos = 950;
private int frameWidth = 230, frameHeight = 274;
private int frameCount = 6;
private int currentFrame = 0;
private long fps;
private long timeThisFrame;
private long lastFrameChangeTime = 0;
private int frameLengthInMillisecond = 60;
private Rect frameToDraw = new Rect(0, 0, frameWidth, frameHeight);
private RectF whereToDraw = new RectF(manXPos, manYPos, manXPos + frameWidth, frameHeight);
public GameView(Context context) {
super(context);
ourHolder = getHolder();
bitmapRunningMan = BitmapFactory.decodeResource(getResources(),
R.drawable.perfectsoldier);
bitmapRunningMan = Bitmap.createScaledBitmap(bitmapRunningMan,
frameWidth * frameCount, frameHeight, false);
}
#Override
public void run() {
while (playing) {
long startFrameTime = System.currentTimeMillis();
update();
this.draw();
Log.d("theOne","its Happennig");
timeThisFrame = System.currentTimeMillis() - startFrameTime;
if (timeThisFrame >= 1) {
fps = 1000 / timeThisFrame;
}
}
}
public void update() {
if (isMoving) {
manXPos = manXPos - runSpeedPerSecond / fps;
if (manXPos > 0) {
//manYPos += (int) frameHeight;
//manXPos = 10;
isMoving=false;
}
if (manYPos + frameHeight > 0) {
// manYPos = 10;
isMoving=false;
}
}
}
public void manageCurrentFrame() {
long time = System.currentTimeMillis();
if (isMoving) {
if (time > lastFrameChangeTime + frameLengthInMillisecond) {
lastFrameChangeTime = time;
currentFrame++;
if (currentFrame >= frameCount) {
currentFrame = 0;
}
}
}
frameToDraw.left = currentFrame * frameWidth;
frameToDraw.right = frameToDraw.left + frameWidth;
}
public void draw() {
if (ourHolder.getSurface().isValid()) {
canvas = ourHolder.lockCanvas();
canvas.drawColor(Color.WHITE);
whereToDraw.set((int) manXPos, (int) manYPos, (int) manXPos
+ frameWidth, (int) manYPos + frameHeight);
manageCurrentFrame();
canvas.drawBitmap(bitmapRunningMan, frameToDraw, whereToDraw, null);
ourHolder.unlockCanvasAndPost(canvas);
}
}
public void pause() {
playing = false;
try {
gameThread.join();
} catch(InterruptedException e) {
Log.e("ERR", "Joining Thread");
}
}
public void resume() {
playing = true;
gameThread = new Thread(this);
gameThread.start();
}
// public boolean onTouchEvent(MotionEvent event) {
// switch (event.getActionMasked() & MotionEvent.ACTION_MASK) {
// case MotionEvent.ACTION_DOWN :
// isMoving = !isMoving;
// break;
// }
//
// return true;
// }
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:focusableInTouchMode="true"
android:color="#000000"
android:weightSum="1" android:background="#ffffff" android:orientation="vertical"
android:id="#+id/theScreen">
<ImageView
android:layout_width="113dp"
android:layout_height="130dp"
android:src="#drawable/thelogo"
android:id="#+id/imageView" android:layout_gravity="center_horizontal"/>
<TextView
android:layout_width="145dp"
android:layout_height="49dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="combat"
android:textSize="30sp"
android:textColor="#000000"
android:id="#+id/nameTextView" android:layout_gravity="right" android:layout_weight="0.06"/>
<EditText
android:layout_width="270dp"
android:layout_height="wrap_content"
android:hint="Username"
android:textColorHint="#808080"
android:textColor="#22272a"
android:id="#+id/userNameEditText" android:layout_gravity="center_horizontal"/>
<Button
android:layout_width="261dp"
android:layout_height="wrap_content"
android:text="Next"
android:drawableRight="#drawable/thearrow"
android:textColor="#000000"
android:onClick="beginMotion"
android:id="#+id/NextButton" android:layout_gravity="center_horizontal" android:background="#638455"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Create an account"
android:id="#+id/textView" android:layout_gravity="center_horizontal" android:layout_weight="0.07"
android:textColor="#22272A"/>
<LinearLayout
android:id="#+id/gameLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
>
</LinearLayout>
</LinearLayout>

You haven't attached myLayout to the activity main layout that you earlier set on setContentView(R.layout.main).
Instead of:
LinearLayout myLayout = new LinearLayout(this);
myLayout.findViewById(R.id.gameLayoutView);
myLayout.addView(gameView);
You should write this:
LinearLayout myLayout = (LinearLayout) findViewById(R.id.gameLayoutView);
myLayout.addView(gameView);

Android: Draw text on ImageView with finger touch

i completed the drawing text on ImageView and i saved the final image in sd card. My problem is, when i am touching the screen to draw the text, my image in the ImageView is disappearing.
Code
import java.io.File;
import java.io.FileOutputStream;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.os.StrictMode;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
public class DrawTextOnImgActivity extends Activity {
private Button btn_save, btn_resume;
private ImageView iv_canvas;
private Bitmap baseBitmap;
private Canvas canvas;
private Paint paint;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_draw_text_on_img);
// The initialization of a brush, brush width is 5, color is red
paint = new Paint();
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
iv_canvas = (ImageView) findViewById(R.id.imageView1);
btn_save = (Button) findViewById(R.id.btn_save);
btn_resume = (Button) findViewById(R.id.btn_resume);
btn_save.setOnClickListener(click);
btn_resume.setOnClickListener(click);
iv_canvas.setOnTouchListener(touch);
}
private View.OnTouchListener touch = new OnTouchListener() {
// Coordinate definition finger touch
float startX;
float startY;
#SuppressLint("ClickableViewAccessibility")
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
// Press the user action
case MotionEvent.ACTION_DOWN:
// The first drawing initializes the memory image, specify the background is white
if (baseBitmap == null) {
baseBitmap = Bitmap.createBitmap(iv_canvas.getWidth(),
iv_canvas.getHeight(), Bitmap.Config.ARGB_8888);
canvas = new Canvas(baseBitmap);
canvas.drawColor(Color.WHITE);
}
// Recording began to touch point coordinate
startX = event.getX();
startY = event.getY();
break;
// The user's finger on the screen of mobile action
case MotionEvent.ACTION_MOVE:
// Record the coordinates of the mobile point
float stopX = event.getX();
float stopY = event.getY();
//According to the coordinates of the two points, drawing lines
canvas.drawLine(startX, startY, stopX, stopY, paint);
// Update start point
startX = event.getX();
startY = event.getY();
// The pictures to the ImageView
iv_canvas.setImageBitmap(baseBitmap);
break;
case MotionEvent.ACTION_UP:
break;
default:
break;
}
return true;
}
};
private View.OnClickListener click = new OnClickListener() {
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_save:
saveBitmap();
break;
case R.id.btn_resume:
resumeCanvas();
break;
default:
break;
}
}
};
/**
* Save the image to the SD card.
*/
protected void saveBitmap() {
try {
// Save the image to the SD card.
File folder = new File(Environment.getExternalStorageDirectory() + "/DrawTextOnImg");
if (!folder.exists()) {
folder.mkdir();
}
File file = new File(Environment.getExternalStorageDirectory()+"/DrawTextOnImg/tempImg.png");
FileOutputStream stream = new FileOutputStream(file);
baseBitmap.compress(CompressFormat.PNG, 100, stream);
Toast.makeText(DrawTextOnImgActivity.this, "Save the picture of success", Toast.LENGTH_SHORT).show();
// Android equipment Gallery application will only at boot time scanning system folder
// The simulation of a media loading broadcast, for the preservation of images can be viewed in Gallery
Intent intent = new Intent();
intent.setAction(Intent.ACTION_MEDIA_MOUNTED);
intent.setData(Uri.fromFile(Environment.getExternalStorageDirectory()));
sendBroadcast(intent);
} catch (Exception e) {
Toast.makeText(DrawTextOnImgActivity.this, "Save failed", Toast.LENGTH_SHORT).show();
e.printStackTrace();
}
}
/**
* Clear the drawing board
*/
protected void resumeCanvas() {
// Manually clear the drawing board, to create a drawing board
if (baseBitmap != null) {
baseBitmap = Bitmap.createBitmap(iv_canvas.getWidth(), iv_canvas.getHeight(), Bitmap.Config.ARGB_8888);
canvas = new Canvas(baseBitmap);
canvas.drawColor(Color.WHITE);
iv_canvas.setImageBitmap(baseBitmap);
Toast.makeText(DrawTextOnImgActivity.this, "Clear the drawing board, can be re started drawing", Toast.LENGTH_SHORT).show();
}
}
}
Manifest
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<protected-broadcast android:name="android.intent.action.MEDIA_MOUNTED" />
By using this code i am writing the text on ImageView but image in the ImageView is disappearing. So, please help me to write the text on image of ImageView

I achieved it by fallowing this code
DrawTextOnImgActivity
import java.io.File;
import java.io.FileOutputStream;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore.Images;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Canvas;
public class DrawTextOnImgActivity extends Activity {
ImageView ivDrawImg;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_draw_text_on_img);
ivDrawImg = (ImageView) findViewById(R.id.iv_draw);
Button btnSave = (Button) findViewById(R.id.btn_save);
Button btnResume = (Button) findViewById(R.id.btn_resume);
btnSave.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
saveImg();
}
});
btnResume.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
}
private void saveImg(){
Bitmap image = Bitmap.createBitmap(ivDrawImg.getWidth(), ivDrawImg.getHeight(), Bitmap.Config.RGB_565);
ivDrawImg.draw(new Canvas(image));
String uri = Images.Media.insertImage(getContentResolver(), image, "title", null);
Log.e("uri", uri);
try {
// Save the image to the SD card.
File folder = new File(Environment.getExternalStorageDirectory() + "/DrawTextOnImg");
if (!folder.exists()) {
folder.mkdir();
//folder.mkdirs(); //For creating multiple directories
}
File file = new File(Environment.getExternalStorageDirectory()+"/DrawTextOnImg/tempImg.png");
FileOutputStream stream = new FileOutputStream(file);
image.compress(CompressFormat.PNG, 100, stream);
Toast.makeText(DrawTextOnImgActivity.this, "Picture saved", Toast.LENGTH_SHORT).show();
// Android equipment Gallery application will only at boot time scanning system folder
// The simulation of a media loading broadcast, for the preservation of images can be viewed in Gallery
/*Intent intent = new Intent();
intent.setAction(Intent.ACTION_MEDIA_MOUNTED);
intent.setData(Uri.fromFile(Environment.getExternalStorageDirectory()));
sendBroadcast(intent);*/
} catch (Exception e) {
Toast.makeText(DrawTextOnImgActivity.this, "Save failed", Toast.LENGTH_SHORT).show();
e.printStackTrace();
}
}
}
DrawView
import java.util.ArrayList;
import java.util.List;
import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;
public class DrawView extends ImageView {
private int color = Color.parseColor("#0000FF");
private float width = 4f;
private List<Holder> holderList = new ArrayList<Holder>();
private class Holder {
Path path;
Paint paint;
Holder(int color, float width) {
path = new Path();
paint = new Paint();
paint.setAntiAlias(true);
paint.setStrokeWidth(width);
paint.setColor(color);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
}
}
public DrawView(Context context) {
super(context);
init();
}
public DrawView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public DrawView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
holderList.add(new Holder(color, width));
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
for (Holder holder : holderList) {
canvas.drawPath(holder.path, holder.paint);
}
}
#SuppressLint("ClickableViewAccessibility")
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
holderList.add(new Holder(color,width));
holderList.get(holderList.size() - 1).path.moveTo(eventX, eventY);
return true;
case MotionEvent.ACTION_MOVE:
holderList.get(holderList.size() - 1).path.lineTo(eventX, eventY);
break;
case MotionEvent.ACTION_UP:
break;
default:
return false;
}
invalidate();
return true;
}
public void resetPaths() {
for (Holder holder : holderList) {
holder.path.reset();
}
invalidate();
}
public void setBrushColor(int color) {
this.color = color;
}
public void setWidth(float width) {
this.width = width;
}
}
Layout (activity_draw_text_on_img)
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FFFFFF" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="250dp"
android:layout_centerInParent="true"
android:background="#FFFFFF" >
<com.app.drawtextonimg.DrawView
android:id="#+id/iv_draw"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:adjustViewBounds="true"
android:src="#drawable/rajamouli" />
</RelativeLayout>
<Button
android:id="#+id/btn_save"
android:layout_width="match_parent"
android:layout_height="40dp"
android:layout_alignParentBottom="true"
android:background="#000000"
android:text="#string/save"
android:textColor="#FFFFFF" />
<Button
android:id="#+id/btn_resume"
android:layout_width="match_parent"
android:layout_height="40dp"
android:background="#000000"
android:text="#string/resume"
android:textColor="#FFFFFF" />
</RelativeLayout>
Manifest file
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
Project link

If I understand your question correctly, I think that you should remove this line from your Case.ACTION_MOVE.
iv_canvas.setImageBitmap(baseBitmap);
By doing this you are resetting your ImageView every time you move on the screen which will cause the ImageView to be just a blank

Switch between activities in Android?

I want to switch between my Main Actvity and my second Activity, but whenever I do it the app shuts down.
So after i click the button1 "Neues Feld", the App should switch to the second activity: feldlayout.class with the layout: feldlayout.xml! The activities are liested in the Android_MAnifest, that's also not the problem...
Thank you for the help! It's working now! I made a new View class, added it to the layout and then it worked fine!
Main Class
package com.example.volleyballapp;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.drawable.Drawable;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.widget.Button;
public class Main_Layout extends Activity {
Button b1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.main_layout);
b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(myhandler);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main__layout, menu);
return true;
}
View.OnClickListener myhandler = new View.OnClickListener(){
public void onClick(View v) {
if(v==b1){
Intent i = new Intent(Main_Layout.this, feldlayout.class);
startActivity(i);
}
}
};}
Main Layout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/background2"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context=".Main_Layout" >
<TextView
android:id="#+id/textView"
android:layout_width="fill_parent"
android:layout_height="250dp"
android:layout_alignParentTop="true"
android:layout_marginLeft="10sp"
android:layout_marginRight="10sp"
android:text=" "
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/farbe" />
<Button
android:id="#+id/button1"
style="#style/ButtonText"
android:layout_below="#id/textView"
android:layout_centerHorizontal="true"
android:background="#drawable/bnt_black"
android:onClick="NeuesFeldClick"
android:text="Neues Feld" />
<TextView
android:layout_width="fill_parent"
android:layout_height="100dp"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text=" "
android:id="#+id/textView2"
android:textColor="#color/farbe"
android:layout_below="#id/button1"/>
<Button
android:id="#+id/button2"
style="#style/ButtonText"
android:layout_below="#id/textView2"
android:layout_centerHorizontal="true"
android:background="#drawable/bnt_black"
android:onClick="LetztesFeldClick"
android:text="Letztes Feld" />
<TextView
android:layout_width="fill_parent"
android:layout_height="100dp"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text=" "
android:id="#+id/textView3"
android:textColor="#color/farbe"
android:layout_below="#id/button2"/>
<Button
android:id="#+id/button3"
style="#style/ButtonText"
android:layout_below="#id/textView3"
android:layout_centerHorizontal="true"
android:background="#drawable/bnt_black"
android:onClick="SavesClick"
android:text="Gespeicherte Felder" />
</RelativeLayout>
Second Activity
package com.example.volleyballapp;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
public class feldlayout extends Activity{
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.feldlayout);
}
private Paint paint = new Paint();
private Path path = new Path();
int count = 1;
public feldlayout(Context context, AttributeSet attrs) {
super();
paint.setAntiAlias(true);
paint.setStrokeWidth(6f); //Breite des Strichs
paint.setColor(Color.BLACK); //Farbe des Strichs
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
}
protected void onDraw(Canvas canvas) {
if ((count%2 != 0)){
canvas.drawPath(path, paint);}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
count++;
if(count%2 != 1){
path.moveTo(eventX, eventY);
return true;
}
if(count%2 != 0){
path.lineTo(eventX, eventY);
break;
}
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_UP:
// nothing to do
break;
default:
return false;
}
// Schedules a repaint.
invalidate();
return true;
}
private void invalidate() {
// TODO Auto-generated method stub
}
}

It's just i tried. your code is working. The problem is you call Constructor in the second Activity. Below one.
public feldlayout(Context context, AttributeSet attrs) {
super();
paint.setAntiAlias(true);
paint.setStrokeWidth(6f); //Breite des Strichs
paint.setColor(Color.BLACK); //Farbe des Strichs
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
}
Please remove this constructor and try again.
Note
Just create a separate class and call the constructor there.

Adding drawable image to background of canvas

I know its possible to paint the background of canvas using
mPaint = new Paint();
mPaint.setColor(Color.RED);
Im just wondering how to i set a permanent background for it. Ive tried using the xml file but nothing happens. Any ideas?
This is the source code of the project, ive been following a tutorial how to do it because im fairly unfamiliar with bitmaps.
Canvas Class
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ImageView;
public class GameBoard extends View{
private int mFlagX = -1;
private int mFlagY = -1;
private Bitmap mBitmap = null;
private Bitmap nBitmap = null;
private Paint mPaint = null;
private boolean isFlagHidden = false;
private int mBoundX = -1;
private int mBoundY = -1;
//play with these values to make the app more or less challenging
public final int CLOSER = 50;
public final int CLOSE = 100;
public GameBoard(Context context, AttributeSet aSet) {
super(context, aSet);
//load our bitmap
mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.star);
//create a paint brush
mPaint = new Paint();
mPaint.setColor(Color.RED);
}
#Override
public void onDraw(Canvas canvas) {
//initialize
if ((mFlagX < 1) || (mFlagY < 1)) {
mFlagX = (int) (getWidth() / 2) - mBitmap.getWidth() / 2;
mFlagY = (int) (getHeight() / 2) - mBitmap.getHeight() / 2;
mBoundX = (int)getWidth() - mBitmap.getWidth();
mBoundY = (int)getHeight() - mBitmap.getHeight();
}
//draw background
canvas.drawRect(0, 0, getWidth(), getHeight(), mPaint);
//draw the flag
if (!isFlagHidden) {
canvas.drawBitmap(mBitmap, mFlagX, mFlagY, null);
}
}
public void hideTheFlag(){
//randomize flag location
mFlagX = (int) Math.ceil(Math.random() * mBoundX);
mFlagY = (int) Math.ceil(Math.random() * mBoundY);
isFlagHidden = true;
//force redraw
invalidate();
}
public void giveUp(){
isFlagHidden = false;
//force redraw
invalidate();
}
public Indicators takeAGuess(float x, float y) {
//this is our "warm" area
Rect prettyClose = new Rect(mFlagX - CLOSE, mFlagY - CLOSE, mFlagX+mBitmap.getWidth() + CLOSE, mFlagY+mBitmap.getHeight() + CLOSE);
//normalize
if (prettyClose.left < 0) prettyClose.left = 0;
if (prettyClose.top < 0) prettyClose.top = 0;
if (prettyClose.right > mBoundX) prettyClose.right = mBoundX;
if (prettyClose.bottom > mBoundY) prettyClose.bottom = mBoundY;
//this is our "hot" area
Rect reallyClose = new Rect(mFlagX - CLOSER, mFlagY - CLOSER, mFlagX+mBitmap.getWidth() + CLOSER, mFlagY+mBitmap.getHeight() + CLOSER);
//normalize
if (reallyClose.left < 0) reallyClose.left = 0;
if (reallyClose.top < 0) reallyClose.top = 0;
if (reallyClose.right > mBoundX) reallyClose.right = mBoundX;
if (reallyClose.bottom > mBoundY) reallyClose.bottom = mBoundY;
//this is the area that contains our flag
Rect bullsEye = new Rect(mFlagX, mFlagY, mFlagX+mBitmap.getWidth(), mFlagY+mBitmap.getHeight());
//check to see where on the board the user pressed
if (bullsEye.contains((int) x, (int)y)) {
//found it
isFlagHidden = false;
invalidate();
return Indicators.BULLSEYE;
} else if (reallyClose.contains((int) x, (int)y)) {
//hot
return Indicators.HOT;
} else if (prettyClose.contains((int)x, (int)y)) {
//warm
return Indicators.WARM;
} else {
//not even close
return Indicators.COLD;
}
}
}
Game Class
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.TextView;
public class FindTheStar extends Activity implements OnTouchListener, OnClickListener{
private GameBoard mGameBoard = null;
private boolean isFlagHidden = false;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_star);
mGameBoard = (GameBoard) findViewById(R.id.Hide_canvas);
mGameBoard.setOnTouchListener(this);
Button b = (Button) findViewById(R.id.the_button);
b.setOnClickListener(this);
}
#Override
public boolean onTouch(View v, MotionEvent event) {
if (v.getId() == R.id.Hide_canvas) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
if (isFlagHidden) {
TextView tv = (TextView)findViewById (R.id.the_label);
switch (mGameBoard.takeAGuess(event.getX(), event.getY())) {
case BULLSEYE:
Button b = (Button) findViewById(R.id.the_button);
isFlagHidden = false;
b.setText("Go Hide!");
tv.setText("You found me!");
tv.setTextColor(Color.GREEN);
break;
case HOT:
tv.setText("You're hot!");
tv.setTextColor(Color.RED);
break;
case WARM:
tv.setText("Getting warm...");
tv.setTextColor(Color.YELLOW);
break;
case COLD:
tv.setText("You're cold.");
tv.setTextColor(Color.BLUE);
break;
}
}
}
return true;
}
return false;
}
#Override
public void onClick(View v) {
if (v.getId() == R.id.the_button) {
TextView tv = (TextView)findViewById (R.id.the_label);
tv.setText("");
Button b = (Button) findViewById(R.id.the_button);
isFlagHidden = !isFlagHidden;
if (isFlagHidden) {
b.setText("Can't find me?");
mGameBoard.hideTheFlag();
} else {
b.setText("Go Hide!");
mGameBoard.giveUp();
}
}
}
}
XML File
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:id="#+id/the_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:textSize="20sp"
android:layout_marginBottom="10dip"
android:text="Lets Play Hide and Seek!"/>
<Button
android:id="#+id/the_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:layout_marginBottom="10dip"
android:text="Go Hide!"/>
<app.autismapp.GameBoard
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/Hide_canvas"/>
</LinearLayout>

yes you can set your permanent background using xml layout..i done this by creating two class.
this is my code in MainACtivity
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
final BrushView view=new BrushView(this);
setContentView(R.layout.mylayout);//removed this one if the paint doesnt work
view.setBackgroundResource(R.drawable.background);//to set background
setContentView(view);// to display the background
and my second class
public class PaintView extends View {
private Paint paint = new Paint();
public LayoutParams params;
public PaintView(Context context) {
super(context);
paint.setAntiAlias(true);
paint.setColor(Color.BLUE);
i hope it gives you an idea

How to add Color Picker in Application?

I have developed an Application , which uses screen as a Slate and finger as a Chalk, which is working properly. But I want to use different color types for chalk.
Here is my Code:
MyDemo.java
package com.example.mydemo;
import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
public class MyDemo extends Activity {
private LinearLayout root;
private Button btnReset;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_demo);
root = (LinearLayout) findViewById(R.id.root);
btnReset = (Button) findViewById(R.id.reset);
final MyImageView view = new MyImageView(this);
view.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.FILL_PARENT));
root.addView(view);
btnReset.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
view.reset();
}
});
}
}
MyImageView.java
package com.example.mydemo;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
import java.util.ArrayList;
import java.util.List;
public class MyImageView extends ImageView implements View.OnTouchListener {
private int id = -1;
private Path path;
private List<Path> paths = new ArrayList<Path>();
private List<PointF> points = new ArrayList<PointF>();
boolean multiTouch = false;
public MyImageView(Context context) {
super(context);
this.setOnTouchListener(this);
}
public void reset() {
paths.clear();
points.clear();
path = null;
id = -1;
invalidate();
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Paint paint = createPen(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
for (Path path : paths) {
canvas.drawPath(path, paint);
}
for (int i = 0; i < points.size(); i++) {
PointF p = points.get(i);
canvas.drawText("" + p.x, p.y, i, createPen(Color.WHITE));
}
}
private PointF copy(PointF p) {
PointF copy = new PointF();
copy.set(p);
return copy;
}
public boolean onTouch(View v, MotionEvent event) {
int action = event.getAction();
switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
multiTouch = false;
id = event.getPointerId(0);
PointF p = getPoint(event, id);
path = new Path();
path.moveTo(p.x, p.y);
paths.add(path);
points.add(copy(p));
break;
case MotionEvent.ACTION_POINTER_DOWN:
multiTouch = true;
for (int i = 0; i < event.getPointerCount(); i++) {
int tId = event.getPointerId(i);
if (tId != id) {
points.add(getPoint(event,i));
}
}
break;
case MotionEvent.ACTION_MOVE:
if (!multiTouch) {
p =getPoint(event, id);
path.lineTo(p.x, p.y);
}
break;
}
invalidate();
return true;
}
private PointF getPoint(MotionEvent event, int i) {
int index = 0;
return new PointF(event.getX(index), event.getY(index));
}
private Paint createPen(int color) {
Paint pen = new Paint();
pen.setColor(color);
float width = 3;
pen.setStrokeWidth(width);
return pen;
}
}
activity_my_demo.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:id="#+id/root" xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button android:id="#+id/reset" android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Reset"
/>
</LinearLayout>
Can any one tell me what should be added or changed in my code so that I can use different colors for Chalk?

You can take the sample in your android folder's..
For the color picker go to in this folder:
android/samples/android-YOURS_VERSION/ApiDemos

Use this, review this code. than your problem will be solve
package com.example.changecolor;
import android.app.Activity;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;
public class MainActivity extends Activity
implements View.OnClickListener, UberColorPickerDialog.OnColorChangedListener {
private int mColor = 0xFFFF0000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Write the version number
PackageManager pm = getPackageManager();
String versionName = "";
try {
PackageInfo pi = pm.getPackageInfo("com.keithwiley.android.ubercolorpickerdemo", 0);
versionName = pi.versionName;
}
catch (Exception e) {
}
TextView textView = (TextView) findViewById(R.id.version);
textView.setText(versionName);
//Initialize the sample
((LinearLayout) findViewById(R.id.LinearLayout)).setBackgroundColor(mColor);
float hsv[] = new float[3];
Color.colorToHSV(mColor, hsv);
if (UberColorPickerDialog.isGray(mColor))
hsv[1] = 0;
if (hsv[2] < .5)
((TextView) findViewById(R.id.sample)).setTextColor(Color.WHITE);
else ((TextView) findViewById(R.id.sample)).setTextColor(Color.BLACK);
//Set up the buttons
Button button = (Button) findViewById(R.id.colorPickerWithTitle);
button.setOnClickListener(this);
button = (Button) findViewById(R.id.colorPickerWithToast);
button.setOnClickListener(this);
}
protected void onPause() {
super.onPause();
}
protected void onResume() {
super.onResume();
}
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
return true;
}
public boolean onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
}
return super.onOptionsItemSelected(item);
}
public void onClick(View v) {
if (v.getId() == R.id.colorPickerWithTitle)
new UberColorPickerDialog(this, this, mColor, true).show();
if (v.getId() == R.id.colorPickerWithToast)
new UberColorPickerDialog(this, this, mColor, false).show();
}
public void colorChanged(int color) {
((LinearLayout) findViewById(R.id.LinearLayout)).setBackgroundColor(mColor=color);
float hsv[] = new float[3];
Color.colorToHSV(mColor, hsv);
//if (UberColorPickerDialog.isGray(mColor))
// hsv[1] = 0;
if (hsv[2] < .5)
((TextView) findViewById(R.id.sample)).setTextColor(Color.WHITE);
else ((TextView) findViewById(R.id.sample)).setTextColor(Color.BLACK);
}
}
And use the color picker class