ThreadingHandlerMessages (basic)

HandlerMessagesActivity.java

import java.lang.ref.WeakReference;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.Toast;

public class HandlerMessagesActivity extends Activity {
	private final static int SET_PROGRESS_BAR_VISIBILITY = 0;
	private final static int PROGRESS_UPDATE = 1;
	private final static int SET_BITMAP = 2;

	private ImageView mImageView;
	private ProgressBar mProgressBar;
	private int mDelay = 500;

	static class UIHandler extends Handler {
		WeakReference<HandlerMessagesActivity> mParent;

		public UIHandler(WeakReference<HandlerMessagesActivity> parent) {
			mParent = parent;
		}

		@Override
		public void handleMessage(Message msg) {
			HandlerMessagesActivity parent = mParent.get();
			if (null != parent) {
				switch (msg.what) {
				case SET_PROGRESS_BAR_VISIBILITY: {
					parent.getProgressBar().setVisibility((Integer) msg.obj);
					break;
				}
				case PROGRESS_UPDATE: {
					parent.getProgressBar().setProgress((Integer) msg.obj);
					break;
				}
				case SET_BITMAP: {
					parent.getImageView().setImageBitmap((Bitmap) msg.obj);
					break;
				}
				}
			}
		}

	}

	Handler handler = new UIHandler(new WeakReference<HandlerMessagesActivity>(
			this));

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		mImageView = (ImageView) findViewById(R.id.imageView);
		mProgressBar = (ProgressBar) findViewById(R.id.progressBar);

		final Button button = (Button) findViewById(R.id.loadButton);
		button.setOnClickListener(new OnClickListener() {
			public void onClick(View v) {
				new Thread(new LoadIconTask(R.drawable.painter, handler))
						.start();
			}
		});

		final Button otherButton = (Button) findViewById(R.id.otherButton);
		otherButton.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				Toast.makeText(HandlerMessagesActivity.this, "I'm Working",
						Toast.LENGTH_SHORT).show();
			}
		});

	}

	private class LoadIconTask implements Runnable {
		private final int resId;
		private final Handler handler;

		LoadIconTask(int resId, Handler handler) {
			this.resId = resId;
			this.handler = handler;
		}

		public void run() {

			Message msg = handler.obtainMessage(SET_PROGRESS_BAR_VISIBILITY,
					ProgressBar.VISIBLE);
			handler.sendMessage(msg);

			final Bitmap tmp = BitmapFactory.decodeResource(getResources(),
					resId);

			for (int i = 1; i < 11; i++) {
				sleep();
				msg = handler.obtainMessage(PROGRESS_UPDATE, i * 10);
				handler.sendMessage(msg);
			}

			msg = handler.obtainMessage(SET_BITMAP, tmp);
			handler.sendMessage(msg);

			msg = handler.obtainMessage(SET_PROGRESS_BAR_VISIBILITY,
					ProgressBar.INVISIBLE);
			handler.sendMessage(msg);
		}

		private void sleep() {
			try {
				Thread.sleep(mDelay);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}

	public ImageView getImageView() {
		return mImageView;
	}

	public ProgressBar getProgressBar() {
		return mProgressBar;
	}

}

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import java.lang.ref.WeakReference;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.ImageView;

import android.widget.ProgressBar;

import android.widget.Toast;

public class HandlerMessagesActivity extends Activity {

private final static int SET_PROGRESS_BAR_VISIBILITY = 0;

private final static int PROGRESS_UPDATE = 1;

private final static int SET_BITMAP = 2;

private ImageView mImageView;

private ProgressBar mProgressBar;

private int mDelay = 500;

static class UIHandler extends Handler {

WeakReference<HandlerMessagesActivity> mParent;

public UIHandler(WeakReference<HandlerMessagesActivity> parent) {

mParent = parent;

}

@Override

public void handleMessage(Message msg) {

HandlerMessagesActivity parent = mParent.get();

if (null != parent) {

switch (msg.what) {

case SET_PROGRESS_BAR_VISIBILITY: {

parent.getProgressBar().setVisibility((Integer) msg.obj);

break;

}

case PROGRESS_UPDATE: {

parent.getProgressBar().setProgress((Integer) msg.obj);

break;

}

case SET_BITMAP: {

parent.getImageView().setImageBitmap((Bitmap) msg.obj);

break;

}

Handler handler = new UIHandler(new WeakReference<HandlerMessagesActivity>(

this));

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

mImageView = (ImageView) findViewById(R.id.imageView);

mProgressBar = (ProgressBar) findViewById(R.id.progressBar);

final Button button = (Button) findViewById(R.id.loadButton);

button.setOnClickListener(new OnClickListener() {

public void onClick(View v) {

new Thread(new LoadIconTask(R.drawable.painter, handler))

.start();

}

});

final Button otherButton = (Button) findViewById(R.id.otherButton);

otherButton.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

Toast.makeText(HandlerMessagesActivity.this, "I'm Working",

Toast.LENGTH_SHORT).show();

}

});

}

private class LoadIconTask implements Runnable {

private final int resId;

private final Handler handler;

LoadIconTask(int resId, Handler handler) {

this.resId = resId;

this.handler = handler;

}

public void run() {

Message msg = handler.obtainMessage(SET_PROGRESS_BAR_VISIBILITY,

ProgressBar.VISIBLE);

handler.sendMessage(msg);

final Bitmap tmp = BitmapFactory.decodeResource(getResources(),

resId);

for (int i = 1; i < 11; i++) {

sleep();

msg = handler.obtainMessage(PROGRESS_UPDATE, i * 10);

handler.sendMessage(msg);

}

msg = handler.obtainMessage(SET_BITMAP, tmp);

handler.sendMessage(msg);

msg = handler.obtainMessage(SET_PROGRESS_BAR_VISIBILITY,

ProgressBar.INVISIBLE);

handler.sendMessage(msg);

}

private void sleep() {

try {

Thread.sleep(mDelay);

} catch (InterruptedException e) {

e.printStackTrace();

}

public ImageView getImageView() {

return mImageView;

}

public ProgressBar getProgressBar() {

return mProgressBar;

}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="match_parent"
        android:layout_height="250dp"
        android:contentDescription="@string/image_desc_string"
        android:scaleType="centerInside" >
    </ImageView>

    <ProgressBar
        android:id="@+id/progressBar"
        style="@android:style/Widget.ProgressBar.Horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:maxHeight="5dip"
        android:minHeight="5dip"
        android:visibility="invisible" >
    </ProgressBar>

    <Button
        android:id="@+id/loadButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/load_icon_string"
        android:textSize="24sp" >
    </Button>

    <Button
        android:id="@+id/otherButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/other_button_string"
        android:textSize="24sp" >
    </Button>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical" >

<ImageView

android:id="@+id/imageView"

android:layout_width="match_parent"

android:layout_height="250dp"

android:contentDescription="@string/image_desc_string"

android:scaleType="centerInside" >

</ImageView>

<ProgressBar

android:id="@+id/progressBar"

style="@android:style/Widget.ProgressBar.Horizontal"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:maxHeight="5dip"

android:minHeight="5dip"

android:visibility="invisible" >

</ProgressBar>

<Button

android:id="@+id/loadButton"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/load_icon_string"

android:textSize="24sp" >

</Button>

<Button

android:id="@+id/otherButton"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/other_button_string"

android:textSize="24sp" >

</Button>

</LinearLayout>