Develop Reference

View Animation for updating progress

I am using a horizontal progress bar and I am trying to animate the bar filling up ( I load the amount of progress before the bar shows up).
This is what I'm doing so far but its not working:
progressBar = (ProgressBar)v.findViewById(R.id.rewards_progress);
Animation animation = new Animation() {
#Override
public void start() {
progressBar.setInterpolator(new AccelerateDecelerateInterpolator());
progressBar.setProgress(currentProgress);
}
};
animation.setDuration(1000);
animation.start();
Any suggestions?

If you just want to update the ProgressBar and as we said in previous comments, you need to do it in another thread, look at this dummy example based in the official Android doc:
package com.example.progressbar;
import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.view.Menu;
import android.widget.ProgressBar;
public class MainActivity extends Activity {
private ProgressBar mProgress;
private static int mProgressStatus = 0;
private Handler mHandler = new Handler();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mProgress = (ProgressBar) findViewById(R.id.rewards_progress);
new Thread(new Runnable() {
public void run() {
while (mProgressStatus < 100) {
doWork();
// Update the progress bar
mHandler.post(new Runnable() {
public void run() {
mProgress.setProgress(mProgressStatus);
}
});
}
}
}).start();
}
private void doWork(){
try {
Thread.sleep(100);
mProgressStatus+=2;
} catch (InterruptedException e) {
}
}
}
However, if you want to animate the ProgressBar update effect, there are several ways to achieve it. One particular way described in this post looks and works pretty good could be easily done by:
package com.example.progressbar;
import android.app.Activity;
import android.os.Bundle;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.ProgressBar;
public class MainActivity extends Activity {
private ProgressBar mProgress;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mProgress = (ProgressBar) findViewById(R.id.rewards_progress);
ProgressBarAnimation anim = new ProgressBarAnimation(mProgress, 0, 100);
anim.setDuration(5000);
mProgress.startAnimation(anim);
}
public class ProgressBarAnimation extends Animation{
private ProgressBar progressBar;
private float from;
private float to;
public ProgressBarAnimation(ProgressBar progressBar, float from, float to) {
super();
this.progressBar = progressBar;
this.from = from;
this.to = to;
}
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
super.applyTransformation(interpolatedTime, t);
float value = from + (to - from) * interpolatedTime;
progressBar.setProgress((int) value);
}
}
}
Note that you should customize ProgressBarAnimation's parameters from and to in order to apply it in a realistic approach.

Need help fixing my class: 'This Handler class should be static or leaks might occur'

I created a simple crossfade image class for use in my app. But... i have an error i can't fix due to lack of knowledge. I found this post This Handler class should be static or leaks might occur: IncomingHandler but i have no clue how to fix this in my class. It is a very straightforward class. Create, initialize and start to use it.
I hope someone can help me fix this warning and while we are at it, some hints and tips on my code or comments are very welcome too ;)
MainActivity.java
package com.example.crossfadeimage;
import android.app.Activity;
import android.os.Bundle;
public class MainActivity extends Activity {
Xfade xfade = new Xfade();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// INIT(current activity, image id's, time between fades, fade speed)
xfade.init(this, new int[]{ R.id.image1, R.id.image2, R.id.image3 }, 3000, 500);
xfade.start();
}
}
Xfade.java
package com.example.crossfadeimage;
import android.app.Activity;
import android.os.Handler;
import android.os.Message;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.widget.ImageView;
public class Xfade {
private Activity activity;
// Handler
private Handler handlerTimer = new Handler();
private static final int UPDATE_STUFF_ON_DIALOG = 999;
private int updateTime;
private Animation fadeIn;
private Animation fadeOut;
public int[] xfadeImages;
public int xfadeCounter = 1;
public void init(Activity thisActivity, int[] images, int time,
int animationSpeed) {
activity = thisActivity;
xfadeImages = images;
updateTime = time;
// Set Animations
fadeIn = new AlphaAnimation(0, 1);
fadeIn.setDuration(animationSpeed);
fadeOut = new AlphaAnimation(1, 0);
fadeOut.setDuration(animationSpeed);
// Hide all images except the first
// which is always visible
for (int image = 1; image < xfadeImages.length; image++) {
ImageView thisImage = (ImageView) activity
.findViewById(xfadeImages[image]);
thisImage.setVisibility(4);
}
}
public void start() {
handlerTimer.removeCallbacks(taskUpdateStuffOnDialog);
handlerTimer.postDelayed(taskUpdateStuffOnDialog, updateTime);
}
private Runnable taskUpdateStuffOnDialog = new Runnable() {
public void run() {
Message msg = new Message();
msg.what = UPDATE_STUFF_ON_DIALOG;
handlerEvent.sendMessage(msg);
// Repeat this after 'updateTime'
handlerTimer.postDelayed(this, updateTime);
}
};
private Handler handlerEvent = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case UPDATE_STUFF_ON_DIALOG: {
crossFade();
}
break;
default: {
super.handleMessage(msg);
}
break;
}
}
};
public void crossFade() {
if (xfadeCounter == 0) {
ImageView lastImage = (ImageView) activity
.findViewById(xfadeImages[xfadeImages.length - 1]);
lastImage.setVisibility(4);
}
if (xfadeCounter < xfadeImages.length) {
ImageView thisImage = (ImageView) activity
.findViewById(xfadeImages[xfadeCounter]);
thisImage.setVisibility(0);
thisImage.startAnimation(fadeIn);
xfadeCounter++;
} else {
// Hide all images except the first
// before fading out the last image
for (int image = 1; image < xfadeImages.length; image++) {
ImageView thisImage = (ImageView) activity
.findViewById(xfadeImages[image]);
thisImage.setVisibility(4);
}
// Fadeout
ImageView lastImage = (ImageView) activity
.findViewById(xfadeImages[xfadeImages.length - 1]);
lastImage.startAnimation(fadeOut);
// LastImage is faded to alpha 0 so it doesn't have to be hidden
// anymore
xfadeCounter = 1;
}
}
}

This allows you to modify views and have your handler set to static.
package com.testing.test;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.TextView;
public class MainActivity extends Activity implements Runnable {
private static final int THREAD_RESULT = 1000;
private TextView mTextView;
private static Handler mHandler;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView = (TextView) findViewById(R.id.text);
}
#Override
protected void onResume() {
super.onResume();
mHandler = new CustomHandler(this);
new Thread(this).start();
}
#Override
public void run() {
// Do some threaded work
// Tell the handler the thread is finished
mHandler.post(new Runnable() {
#Override
public void run() {
mHandler.sendEmptyMessage(THREAD_RESULT);
}
});
}
private class CustomHandler extends Handler {
private MainActivity activity;
public CustomHandler(MainActivity activity) {
super();
this.activity = activity;
}
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case THREAD_RESULT:
activity.mTextView.setText("Success!");
break;
}
}
}
}

Display progress bar while loading

I have one button in the main.xml which will link to another xml which include information from server. I include progress bar to avoid the blank screen while the system is loading the information. i already done the code as below but it's still not the things i wanted. the code below will "WAIT" for 1000 ms then only will execute the next code. how can i modify it so that the loading "WAIT TIME" will depends on the internet speed, if internet connection is slow, then the progress-bar-screen will show longer.
package com.android.myApps;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.TextView;
public class MainScr extends Activity {
private final int WAIT_TIME = 1000;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.MainScr);
}
public void onClickCategory(View view)
{
findViewById(R.id.mainSpinner1).setVisibility(View.VISIBLE);
new Handler().postDelayed(new Runnable(){
#Override
public void run() {
Intent mainIntent = new Intent(MainScr.this, Category.class);
MainScr.this.startActivity(mainIntent);
MainScr.this.finish();
}
}, WAIT_TIME);
}
}

The mistake you are doing here is you are dumping specific time into your code
You never know how much it will take to get response.
You should follow following approach
Step 1 Show progress dialog on screen
Step 2 Let download take its own time.But it should be done in new thread
Step 3 Once download is complete it will raise message that task is done,now remove that
progress dialog and proceed.
I am pasting sample code here.Hope it will help you.
package com.android.myApps;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
public class MainScr extends Activity
{
private Handler handler;
private ProgressDialog progress;
private Context context;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
context = AncActivity.this;
progress = new ProgressDialog(this);
progress.setTitle("Please Wait!!");
progress.setMessage("Wait!!");
progress.setCancelable(false);
progress.setProgressStyle(ProgressDialog.STYLE_SPINNER);
handler = new Handler()
{
#Override
public void handleMessage(Message msg)
{
progress.dismiss();
Intent mainIntent = new Intent(context, Category.class);
startActivity(mainIntent);
super.handleMessage(msg);
}
};
progress.show();
new Thread()
{
public void run()
{
// Write Your Downloading logic here
// at the end write this.
handler.sendEmptyMessage(0);
}
}.start();
}
}

Did you try Asyntask? Your doing process will be update in UI.
public final class HttpTask
extends
AsyncTask<String/* Param */, Boolean /* Progress */, String /* Result */> {
private HttpClient mHc = new DefaultHttpClient();
#Override
protected String doInBackground(String... params) {
publishProgress(true);
// Do the usual httpclient thing to get the result
return result;
}
#Override
protected void onProgressUpdate(Boolean... progress) {
// line below coupled with
// getWindow().requestFeature(Window.FEATURE_INDETERMINATE_PROGRESS)
// before setContentView
// will show the wait animation on the top-right corner
MyActivity.this.setProgressBarIndeterminateVisibility(progress[0]);
}
#Override
protected void onPostExecute(String result) {
publishProgress(false);
// Do something with result in your activity
}
}

Added textview code crashed the application in emulator

I am working on a homework project that requires to have a textview counter along with an existing progress bar. I added the textview code to java file and main.xml. When I run it in the emulator I get "The application xxx has stopped unexpectedly" message. I have not been able to figure out the cause. Here is my code:
(Code indentation is not entirely proper. I will strive to make it so)
Source file:
package com.mypackage;
import android.app.Activity;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MyButtonActivity extends Activity {
static final int PROGRESS_DIALOG = 0;
Button button;
ProgressThread progressThread;
ProgressDialog progressDialog;
TextView Int;
/** Called when the activity is first created. */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Int = (TextView)findViewById(R.id.Int);
// Setup the button that starts the progress dialog
button = (Button) findViewById(R.id.myButton);
button.setOnClickListener(new Button.OnClickListener(){
public void onClick(View v) {
// Show dialog managed by this activity
showDialog(PROGRESS_DIALOG);
}
});
}
// Callback for creating dialogs that are managed (saved and restored)
// for you by the activity.
protected Dialog onCreateDialog(int id) {
switch(id) {
case PROGRESS_DIALOG:
progressDialog = new ProgressDialog(MyButtonActivity.this);
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressDialog.setMessage("Loading...");
// Create and start the handler
progressThread = new ProgressThread(handler);
progressThread.start();
return progressDialog;
default:
return null;
}
}
// Define the Handler that receives messages from the thread and update
// the progress
final Handler handler = new Handler() {
public void handleMessage(Message msg) {
int total = msg.getData().getInt("total");
progressDialog.setProgress(total);
Int.setText(String.valueOf(total));
if (total >= 100){
dismissDialog(PROGRESS_DIALOG);
progressThread.setState(ProgressThread.STATE_DONE);
}
}
};
/** Nested class that performs progress calculations (counting) */
private class ProgressThread extends Thread {
Handler mHandler;
final static int STATE_DONE = 0;
final static int STATE_RUNNING = 1;
int mState;
int total;
ProgressThread(Handler h) {
mHandler = h;
}
public void run() {
mState = STATE_RUNNING;
total = 0;
while (mState == STATE_RUNNING) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
Log.e("ERROR", "Thread Interrupted");
}
Message msg = mHandler.obtainMessage();
Bundle b = new Bundle();
b.putInt("total", total);
msg.setData(b);
mHandler.sendMessage(msg);
total++;
}
}
/* sets the current state for the thread,
* used to stop the thread */
public void setState(int state) {
mState = state;
}
}
I only added a few lines to existing code (including a textview to main.xml). So is it more involved than simply adding textview code to implement the textview counter? Given that it is one of first projects in my intro level course, I think simply adding a textview should satisfy the requirement. Please enlighten. Thanks!

I tested your code and it worked for me! Did you try to:
Under Eclipse bar Project->Clean Project
Right click on your project Android Tools->Fix Project Properties

TextView Text Not Updating

package com.aviyehuda.test.multithreading;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MultithreadingTest extends Activity {
Button btn;
private Handler myHandler;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn = (Button) findViewById(R.id.Button01);
}
public void buttonClicked(View v) {
myHandler = new Handler();
MyThread mThread = new MyThread();
mThread.start();
}
class MyThread extends Thread {
#Override
public void run() {
for (int i = 0; i < 30; i++) {
myHandler.post(new NewThreaad(i));
}
}
}
class NewThreaad implements Runnable{
int i;
public NewThreaad(int n) {
i=n;
}
#Override
public void run() {
((TextView) findViewById(R.id.TextView01)).setText("Hello:"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
I have code mentioned above but getting result Hello29 on TextView but i want Hello1,Hello2,hello3.................Hello29 one by one automatically
Please give me hint what I am doing wrong

A couple of things.
First, after changing the text, you should call invalidate on the TextView to force a refresh.
Second, to do operation on the UI, you should run that in the UI thread. Use runOnUiThread

Well, the main problem is that you're not appending you are overwriting. Instead of
((TextView) findViewById(R.id.TextView01)).setText("Hello:"+i);
do
TextView tv = ((TextView) findViewById(R.id.TextView01));
String text = tv.getText().toString();
tv.setText(text + " Hello:" + i);

You need to move the 500 ms delay to your for-loop, between posting of messages. I think you're expecting the messages to execute sequentially one after the other, but they don't, which is the reason you just see the result of the last one.