ColorMatrix.setConcat() to combine ColorMatrixes

The exercise "Set the rotation on a color axis of Bitmap with ColorMatrix" create rotated ColorMatrix for one color only, not all. We can create ColorMatrix from more than one by calling ColorMatrix.setConcat().

ColorMatrix.setConcat() to combine ColorMatrixs


package com.example.androiddrawbitmap;

import java.io.FileNotFoundException;

import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;

public class MainActivity extends Activity {

Button btnLoadImage;
ImageView imageResult;
SeekBar rotBarRed, rotBarGreen, rotBarBlue;
TextView rotText;

final int RQS_IMAGE1 = 1;

Uri source;
Bitmap bitmapMaster;
Canvas canvasMaster;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

btnLoadImage = (Button) findViewById(R.id.loadimage);
imageResult = (ImageView) findViewById(R.id.result);

btnLoadImage.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View arg0) {
Intent intent = new Intent(
Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(intent, RQS_IMAGE1);
}
});

rotText = (TextView) findViewById(R.id.textRot);
rotBarRed = (SeekBar) findViewById(R.id.rotbarred);
rotBarGreen = (SeekBar) findViewById(R.id.rotbargreen);
rotBarBlue = (SeekBar) findViewById(R.id.rotbarblue);
rotBarRed.setOnSeekBarChangeListener(seekBarChangeListener);
rotBarGreen.setOnSeekBarChangeListener(seekBarChangeListener);
rotBarBlue.setOnSeekBarChangeListener(seekBarChangeListener);

}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);

if (resultCode == RESULT_OK) {
switch (requestCode) {
case RQS_IMAGE1:
source = data.getData();

try {
bitmapMaster = BitmapFactory
.decodeStream(getContentResolver().openInputStream(
source));

rotBarRed.setProgress(0);
rotBarGreen.setProgress(0);
rotBarBlue.setProgress(0);

loadBitmapRotate();

} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

break;
}
}
}

OnSeekBarChangeListener seekBarChangeListener = new OnSeekBarChangeListener() {

@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub

}

@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub

}

@Override
public void onStopTrackingTouch(SeekBar seekBar) {
loadBitmapRotate();
}
};

private void loadBitmapRotate() {
if (bitmapMaster != null) {

float rotRed = (float) rotBarRed.getProgress();
float rotGreen = (float) rotBarGreen.getProgress();
float rotBlue = (float) rotBarBlue.getProgress();

rotText.setText("setRotate: " + String.valueOf(rotRed) + ", "
+ String.valueOf(rotGreen) + ", " + String.valueOf(rotBlue));

Bitmap bitmapColorScaled = updateRot(bitmapMaster, rotRed,
rotGreen, rotBlue);

imageResult.setImageBitmap(bitmapColorScaled);
}
}

private Bitmap updateRot(Bitmap src, float degreesRed, float degreesGreen,
float degreesBlue) {

int w = src.getWidth();
int h = src.getHeight();

Bitmap bitmapResult = Bitmap
.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas canvasResult = new Canvas(bitmapResult);
Paint paint = new Paint();

ColorMatrix colorMatrixRed = new ColorMatrix();
colorMatrixRed.setRotate(0, degreesRed);
ColorMatrix colorMatrixGreen = new ColorMatrix();
colorMatrixGreen.setRotate(1, degreesGreen);
ColorMatrix colorMatrixBlue = new ColorMatrix();
colorMatrixBlue.setRotate(2, degreesBlue);
ColorMatrix colorMatrixConcat = new ColorMatrix();
colorMatrixConcat.setConcat(colorMatrixRed, colorMatrixGreen);
colorMatrixConcat.setConcat(colorMatrixConcat, colorMatrixBlue);

ColorMatrixColorFilter filter = new ColorMatrixColorFilter(
colorMatrixConcat);
paint.setColorFilter(filter);
canvasResult.drawBitmap(src, 0, 0, paint);

return bitmapResult;
}
}


<LinearLayout 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: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"
tools:context=".MainActivity" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:autoLink="web"
android:text="http://android-er.blogspot.com/"
android:textStyle="bold" />

<Button
android:id="@+id/loadimage"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Load Image 1" />

<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent" >

<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >

<ImageView
android:id="@+id/result"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:background="@android:color/background_dark"
android:scaleType="centerInside" />

<TextView
android:id="@+id/textRot"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="ColorMatrix Rotate" />

<SeekBar
android:id="@+id/rotbarred"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="360"
android:progress="0" />
<SeekBar
android:id="@+id/rotbargreen"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="360"
android:progress="0" />
<SeekBar
android:id="@+id/rotbarblue"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="360"
android:progress="0" />
</LinearLayout>
</ScrollView>

</LinearLayout>


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