Android example code using ColorFilter

MainActivity.java

package com.blogspot.android_er.androidcolorfilter;

import android.graphics.ColorFilter;
import android.graphics.ColorMatrixColorFilter;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.ImageView;
import android.widget.SeekBar;

public class MainActivity extends AppCompatActivity {

 ImageView imageView;
 SeekBar redBar, greenBar, blueBar;

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

 imageView = (ImageView)findViewById(R.id.iv);
 redBar = (SeekBar)findViewById(R.id.redbar);
 greenBar = (SeekBar)findViewById(R.id.greenbar);
 blueBar = (SeekBar)findViewById(R.id.bluebar);

 redBar.setOnSeekBarChangeListener(colorBarChangeListener);
 greenBar.setOnSeekBarChangeListener(colorBarChangeListener);
 blueBar.setOnSeekBarChangeListener(colorBarChangeListener);

 setColorFilter(imageView);
 }

 SeekBar.OnSeekBarChangeListener colorBarChangeListener
 = new SeekBar.OnSeekBarChangeListener(){

 @Override
 public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
 setColorFilter(imageView);
 }

 @Override
 public void onStartTrackingTouch(SeekBar seekBar) {

 }

 @Override
 public void onStopTrackingTouch(SeekBar seekBar) {

 }
 };

 private void setColorFilter(ImageView iv){

 /*
 * 5x4 matrix for transforming the color+alpha components of a Bitmap.
 * The matrix is stored in a single array, and its treated as follows:
 * [ a, b, c, d, e,
 * f, g, h, i, j,
 * k, l, m, n, o,
 * p, q, r, s, t ]
 *
 * When applied to a color [r, g, b, a], the resulting color is computed
 * as (after clamping)
 * R = a*R + b*G + c*B + d*A + e;
 * G = f*R + g*G + h*B + i*A + j;
 * B = k*R + l*G + m*B + n*A + o;
 * A = p*R + q*G + r*B + s*A + t;
 */

 float redValue = ((float)redBar.getProgress())/255;
 float greenValue = ((float)greenBar.getProgress())/255;
 float blueValue = ((float)blueBar.getProgress())/255;

 float[] colorMatrix = {
 redValue, 0, 0, 0, 0, //red
 0, greenValue, 0, 0, 0, //green
 0, 0, blueValue, 0, 0, //blue
 0, 0, 0, 1, 0 //alpha
 };

 ColorFilter colorFilter = new ColorMatrixColorFilter(colorMatrix);
 iv.setColorFilter(colorFilter);
 }

}

layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
 
 
 android_layout_width="match_parent"
 android_layout_height="match_parent"
 android_padding="16dp"
 android_orientation="vertical"
 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" />

 <ImageView
 android_id="@+id/iv"
 android_layout_width="wrap_content"
 android_layout_height="wrap_content"
 android_src="@mipmap/ic_launcher"/>

 <SeekBar
 android_id="@+id/redbar"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_max="255"
 android_progress="255"/>
 <SeekBar
 android_id="@+id/greenbar"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_max="255"
 android_progress="255"/>
 <SeekBar
 android_id="@+id/bluebar"
 android_layout_width="match_parent"
 android_layout_height="wrap_content"
 android_max="255"
 android_progress="255"/>
</LinearLayout>

Related:
- Convert ImageView to black and white, and set brightness, using ColorFilter

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