Develop Reference

Adjust size and gap between FancyButton placed on LinearLayout

I have placed programmatically generated FancyButtons on LinearLayout. But, the generated buttons are placed too compactly, in other words, there is no separation between two successive buttons. Also, I want the buttons to stretch entire with of the layout. I tried btnWordList.setMinimumWidth(MATCH_PARENT) without any result. Please find the code below.
FlexDict.java
package in.dipanjan.flexdict;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.graphics.Color;
import android.content.Intent;
import android.widget.LinearLayout;
import android.graphics.PixelFormat;
import mehdi.sakout.fancybuttons.FancyButton;
import android.support.v7.app.ActionBarActivity;
public class FlexDict extends ActionBarActivity implements View.OnClickListener {
#Override
public void onAttachedToWindow() {
super.onAttachedToWindow();
Window window = getWindow();
window.setFormat(PixelFormat.RGBA_8888);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
int listCount, wordLists = 5;
/* http://stackoverflow.com/questions/19078461/android-null-pointer-exception-findviewbyid */
setContentView(R.layout.activity_flex_dict);
LinearLayout container = (LinearLayout)findViewById(R.id.container);
for(listCount = 1; listCount <= wordLists; listCount++)
{
/* https://github.com/medyo/fancybuttons */
FancyButton btnWordList = new FancyButton(this);
btnWordList.setId(listCount);
btnWordList.setText("WordList " + listCount);
btnWordList.setBackgroundColor(Color.parseColor("#3b5998"));
btnWordList.setFocusBackgroundColor(Color.parseColor("#5474b8"));
btnWordList.setTextSize(20);
btnWordList.setIconResource("\uf04b");
btnWordList.setRadius(10);
btnWordList.setOnClickListener(this);
container.addView(btnWordList);
}
setContentView(container);
}
#Override
public void onClick(View view) {
int wordList = view.getId();
/*
* http://www.java-samples.com/showtutorial.php?tutorialid=1525
* http://stackoverflow.com/questions/7980627/pressing-back-button-did-not-go-back-to-previous-activity-android
*/
Bundle params = new Bundle();
params.putInt("WordList", wordList);
Intent intent = new Intent(this, ShowList.class);
intent.putExtras(params);
startActivity(intent);
}
}
activity_flex_dict.xml
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
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:background="#drawable/radialback">
</LinearLayout>
UI
http://s26.postimg.org/rkb0r4ys9/Fancy_Button.png

You need to setLayoutParams on your View.
i.e. btnWordList.setLayoutParams(new LinearLayout.LayoutParams(MATCH_PARENT, WRAP_CONTENT));
You need to set layout params for any view even if instantiated in XML or Programatically.
http://developer.android.com/reference/android/view/View.html#setLayoutParams(android.view.ViewGroup.LayoutParams)
Set the layout parameters associated with this view. These supply parameters to the parent of this view specifying how it should be arranged. There are many subclasses of ViewGroup.LayoutParams, and these correspond to the different subclasses of ViewGroup that are responsible for arranging their children.

You need to set a margin between your buttons to make a gab between your buttons. and set your width to match_parent to make the button stretch to the width of the layout
int marginBottom = (int) TypedValue.applyDimension(
TypedValue.COMPLEX_UNIT_DIP,
5,
r.getDisplayMetrics()
);
for(listCount = 1; listCount <= wordLists; listCount++)
{
/* https://github.com/medyo/fancybuttons */
FancyButton btnWordList = new FancyButton(this);
btnWordList.setId(listCount);
LayoutParams params = new LayoutParams(
LayoutParams.MATCH_PARENT,
LayoutParams.WRAP_CONTENT
);
params.setMargins(0, 0, 0, marginBottom);
btnWordList.setLayoutParams(params);
btnWordList.setText("WordList " + listCount);
btnWordList.setBackgroundColor(Color.parseColor("#3b5998"));
btnWordList.setFocusBackgroundColor(Color.parseColor("#5474b8"));
btnWordList.setTextSize(20);
btnWordList.setIconResource("\uf04b");
btnWordList.setRadius(10);
btnWordList.setOnClickListener(this);
container.addView(btnWordList);
}

You can use LayoutParam with margin
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(MATCH_PARENT, WRAP_CONTENT);
lp.bottumMargin = 2;
// or
lp.setMargins(0,0,0,2);
btnWordList.setLayoutParams(lp);

Programmatically creating a horizontalscrollview not working

I am trying to create a horizontalscrollview in the onCreate() method of my first activity, since I want to make a large number of textviews to scroll through. Here is what I have so far:
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.ViewGroup.LayoutParams;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.TextView;
public class MainActivity extends Activity {
LinearLayout linscrollview;
HorizontalScrollView scrollview;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
scrollview = (HorizontalScrollView) findViewById(R.id.scrollview_layout);
linscrollview = new LinearLayout(this);
for(int i=0; i<5; i++) {
TextView tv = new TextView(this);
tv.setWidth(LayoutParams.WRAP_CONTENT);
tv.setHeight(LayoutParams.WRAP_CONTENT);
tv.setText("" + i);
tv.setTextSize(20);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
params.setMargins(10, 0, 10, 0);
tv.setLayoutParams(params);
tv.setId(i);
linscrollview.addView(tv);
}
scrollview.addView(linscrollview);
}
#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, menu);
return true;
}
}
I am not getting any errors, however no textviews are showing up.

Your problem is likely to do with the setWidth and setHeight methods. They set the exact value of the TextView width and height in pixels as described in the documentation:
Makes the TextView exactly this many pixels wide. You could do the
same thing by specifying this number in the LayoutParams.
http://developer.android.com/reference/android/widget/TextView.html#setWidth(int)
What you want to do is set the LayoutParams for the TextView as you are already going slightly further down your code. So just get rid of those two method calls and it should work.

this s a chunk of code to implement horizontal scrolling for textview, modify the same according to requirements.
textView.setHorizontallyScrolling(true);
textView.setSingleLine(true);
textView.setMovementMethod(new ScrollingMovementMethod());
textView.setHorizontalScrollBarEnabled(true);
textView.setSelected(true);

Please do like this
linscrollview .setOrientation(LinearLayout.HORIZONTAL);
and ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(FILL_PARENT, WRAP_CONTENT);

My coding here. it will gives you list like horizonatal listview
String[] name={"PRASHANT","PRASHANT","PRASHANT","PRASHANT","PRASHANT","PRASHANT","PRASHANT"} ;
myLInearLayoutmain =(LinearLayout) findViewById(R.id.linearLayoutmain);
for(int i =0;i<6;i++)
{
LinearLayout li=new LinearLayout(getApplicationContext());
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
li.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams params1 = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
LinearLayout.LayoutParams paramsnew = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
params1.setMargins(30, 20, 30, 0);
//add textView
valueTV = new TextView(this);
valueTV.setText(""+name[i]);
valueTV.setId(5);
valueTV.setLayoutParams(paramsnew);
valueTV.setGravity(Gravity.CENTER);
// adding Button to linear
valueB = new Button(this);
valueB.setText(""+name[i]);
valueB.setId(i);
valueB.setLayoutParams(params);
valueB.setOnClickListener(this);
valueB.setGravity(Gravity.CENTER);
//add the textView and the Button to LinearLayout
li.addView(valueTV);
li.addView(valueB);
li.addView(img);
li.setLayoutParams(params1);
myLInearLayoutmain.addView(li);
}

Adding multiple framelayout in a linearlayout programmatically

I need to overlap an image view with textview. And this combined view will be repeated 100 times in a LinearLayout. I was thinking of using FrameLayout in LinearLayout and Repeating the FrameLayout in LinearLayout 100 times when FrameLayout holds the imageview and textview overlapped.
Need to do this programatically not from xml file.
I added the image and textview to framelayout first then tried to add the framelayout to linearlayout. But it says : the specified child has already a parent.. so not working. Can you please show me in code? Thanks for your help.
it is going to be like this, but need to be done programmaticaly
---linear layout--------------
------------------------------
|frame layout----------------|
||txt view on top of img view|
------------------------------
frame layout will be repeated|
---/end of linear layout------
Also here is the separated code:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
LinearLayout dynamicview = (LinearLayout) findViewById(R.id.main_layout);
FrameLayout barFrameLayout = new FrameLayout(this);
FrameLayout.LayoutParams params = new FrameLayout.LayoutParams(
LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT,
Gravity.CENTER);
barFrameLayout.setLayoutParams(params);
LinearLayout.LayoutParams slparams1 = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
for (int i = 65; i <= 75; i++) {
TextView catTV = new TextView(this);
catTV.setLayoutParams(slparams1);
catTV.setText("===" + Character.toString((char) i) + "===");
catTV.setTextSize(32);
ImageView iv = new ImageView(this);
iv.setImageResource(R.drawable.ic_launcher);
iv.setLayoutParams(slparams1);
barFrameLayout.addView(catTV);
barFrameLayout.addView(iv);
dynamicview.addView(barFrameLayout);
}
}

Here is the code to demonstrate what you are trying to achieve. I have used RelativeLayout, which is very flexible, you can position the elements easily relative to others.( if you need to change to FrameLayout you can change ).
import android.content.Context;
import android.util.AttributeSet;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;
public class ExampleLayout extends LinearLayout{
public ExampleLayout(Context context,AttributeSet attrs){
super(context,attrs);
for(int i =0; i< 100; i++){
RelativeLayout childLayout = new RelativeLayout(context);
ImageView img = new ImageView(context);
TextView text = new TextView(context);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
childLayout.addView(img, params);
params = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
childLayout.addView(text, params);
LinearLayout.LayoutParams parentParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
this.addView(childLayout,parentParams);
}
}
}
You can then use the ExampleLayout class to add it to any of the layout.xml file.

FrameLayout is designed to block out an area on the screen to display
a single item
(source: http://developer.android.com/reference/android/widget/FrameLayout.html).
Anyway, you have to create new FrameLayouts not use the same.
When you're doing:
barFrameLayout.addView(catTV);
barFrameLayout.addView(iv);
dynamicview.addView(barFrameLayout);
you're always adding these new objects (catTV and iv) to the same instance of a FrameLayout (barFrameLayout).
I don't think that's what you wanted to do.

how to draw a ImageView in the middle of the screen? (programatically)

I want to draw a simple ImageView in the middle of the screen, horizontally and vertically. But i want to do it without using XML files, i need to do it programatically.
I tryed with the next code, but it doesn't works fine, it draws the image a little to the right and a little to the bottom. How to solve it?
ARImage = new ImageView(getApplicationContext());
ARImage.setImageResource(R.drawable.x);
rl.addView(ARImage); //rl is the relative layout that it's inserted into a frame layout
Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int w = display.getWidth();
int h = display.getHeight();
RelativeLayout.LayoutParams position = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
position.leftMargin = (int)(w/2);
position.topMargin = (int)(h/2);
ARImage.setLayoutParams(position);

It works for me like this:
package pete.android.study;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.Display;
import android.view.WindowManager;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.RelativeLayout.LayoutParams;
public class Main extends Activity {
/*
* (non-Javadoc)
* #see android.app.Activity#onCreate(android.os.Bundle)
*/
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ImageView ARImage = new ImageView(getApplicationContext());
ARImage.setImageResource(R.drawable.icon);
RelativeLayout rl = new RelativeLayout(this);
Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int w = display.getWidth();
int h = display.getHeight();
RelativeLayout.LayoutParams position = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
ARImage.setLayoutParams(position);
position.addRule(RelativeLayout.CENTER_IN_PARENT);
rl.addView(ARImage, position);
setContentView(rl);
}
}

Try to use
position.leftMargin = (int)(w/2 - whalf);
position.topMargin = (int)(h/2 - hhalf);
where whalf and hhalf are halfs of your image parameters.

I don't think you can set the left and top margin like that:
position.leftMargin = (int)(w/2);
position.topMargin = (int)(h/2);
Try setting the margins like this:
position.setMargins((int)(w/2), (int)(h/2), 0, 0); // left, top, right, bottom

Knowing that it is inside of RelativeLayout, you can place it in center of this layout:
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
lp.addRule(RelativeLayout.CENTER_IN_PARENT);
rl.addView(ARImage, lp);

Refreshing a LinearLayout after adding a view

I'm trying to add views dynamically to a linearlayout.
I see through getChildCount() that the views are added to the layout, but even calling invalidate() on the layout doesn't give me the childs showed up.
Am I missing something?

A couple of things you can check in your code:
On the View that is being added, check that you call its setLayoutParameter method with an appropriate ViewGroup.LayoutParameter.
When you adding the new Views, make sure you are doing it on the UI thread. To do this, you can use the parent View's post method.
This self contained example adds a TextView after a short delay when it starts:
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.os.Bundle;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;
public class ProgrammticView extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
final LinearLayout layout = new LinearLayout(this);
layout.setLayoutParams(new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT,
ViewGroup.LayoutParams.FILL_PARENT));
setContentView(layout);
// This is just going to programatically add a view after a short delay.
Timer timing = new Timer();
timing.schedule(new TimerTask() {
#Override
public void run() {
final TextView child = new TextView(ProgrammticView.this);
child.setText("Hello World!");
child.setLayoutParams(new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT));
// When adding another view, make sure you do it on the UI
// thread.
layout.post(new Runnable() {
public void run() {
layout.addView(child);
}
});
}
}, 5000);
}
}

I had the same problem and noticed that my overriden onMeasure() method wasn't called after the invalidate. So I created my own subroutine in the LinearLayout and called it before the invalidate() method.
Here is the code for an vertical LinearLayout:
private void measure() {
if (this.getOrientation() == LinearLayout.VERTICAL) {
int h = 0;
int w = 0;
this.measureChildren(0, 0);
for (int i = 0; i < this.getChildCount(); i++) {
View v = this.getChildAt(i);
h += v.getMeasuredHeight();
w = (w < v.getMeasuredWidth()) ? v.getMeasuredWidth() : w;
}
height = (h < height) ? height : h;
width = (w < width) ? width : w;
}
this.setMeasuredDimension(width, height);
}

I spent a lot of time to solve this problem too. And I found a simple method of refresh LinearLayout in 3 lines of code
You must set transperent color in style.xml
<color name="transparent">#00000000</color>
And in the code just call to set background
LinearLayout ll = (LinearLayout) findViewById(R.id.noteList);
ll.setBackgroundColor(getResources().getColor(R.color.transparent));
ll.invalidate();
If you has drawable background call
ll.setBackgroundResource(R.drawable.your_drawable);