android - 更改android中的像素颜色

Question

testButton.setOnClickListener(new Button.OnClickListener(){

        @Override
        public void onClick(View v) 
        {
            Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);for (int i = 0; i < mutableBitmap.getWidth(); i++) 
                {
                    for (int j = 0; j < mutableBitmap.getHeight(); j++) 
                    {
                        int pixel = mutableBitmap.getPixel(i, j);
                        // get red color value
                        int red = Color.red(pixel);
                        int color = Color.argb(0xFF, red, 0, 0);
                        mutableBitmap.setPixel(i, j, color);
                        imageView.setImageBitmap(mutableBitmap);
                    }
                }
        }


        });

我正在尝试仅使用红色值更改像素颜色。因此，我从给定的像素中获取红色值，然后尝试仅用该红色值替换相同的像素。该程序运行成功，但是当我单击按钮时它崩溃了。谁能告诉我我做错了什么

LOGCAT 错误

12-03 15:16:57.228: E/AndroidRuntime(5103): FATAL EXCEPTION: main
12-03 15:16:57.228: E/AndroidRuntime(5103): java.lang.IllegalStateException
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.graphics.Bitmap.setPixel(Bitmap.java:1002)
12-03 15:16:57.228: E/AndroidRuntime(5103): at com.example.imaging.AndroidCamera$7.onClick(AndroidCamera.java:216)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.view.View.performClick(View.java:3511)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.view.View$PerformClick.run(View.java:14109)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.os.Handler.handleCallback(Handler.java:605)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.os.Handler.dispatchMessage(Handler.java:92)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.os.Looper.loop(Looper.java:137)
12-03 15:16:57.228: E/AndroidRuntime(5103): at android.app.ActivityThread.main(ActivityThread.java:4424)
12-03 15:16:57.228: E/AndroidRuntime(5103): at java.lang.reflect.Method.invokeNative(Native Method
12-03 15:16:57.228: E/AndroidRuntime(5103): at java.lang.reflect.Method.invoke(Method.java:511)
12-03 15:16:57.228: E/AndroidRuntime(5103): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
12-03 15:16:57.228: E/AndroidRuntime(5103): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
12-03 15:16:57.228: E/AndroidRuntime(5103): at dalvik.system.NativeStart.main(Native Method)

Answer 1

您正在尝试修改不可变位图的像素。您无法修改不可变位图的像素。如果您尝试，它将抛出 IllegalStateException。

使用下面的方法从资源中获取可变位图

public static Bitmap getMutableBitmap(Resources resources,int resId) {
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inMutable = true;
    return BitmapFactory.decodeResource(resources, resId, options);
}

或使用

    Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);

从不可变位图中获取可变位图