ImageView 实现Android colorPikcer 选择器的示例代码

2019-10-22 18:25:30

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本文介绍了ImageView 实现Android colorPikcer 选择器的示例代码，分享给大家，具体如下：

Android colorPikcer 选择器

Android,colorPikcer,选择器,color

环形的ColorPicker，主要思路是:

Color 选在放在ImageView 的background上面，根据点击的位置判断选择的颜色。
重写onTouch，在onTouch 里面判断点击点的颜色。
根据当前选择的颜色设置图片的src.

获取Bitmap

在 ColorPickerView 构造函数中初始化 Bitmap。因为getBackground有多种drawable，然后获取Bitmap 的方式也不用，

void init(Context context, @Nullable AttributeSet attrs, int defStyleAttr){    Drawable drawable = getBackground();    if(drawable instanceof BitmapDrawable){      mBitmap = ((BitmapDrawable) drawable).getBitmap();    } else if(drawable instanceof VectorDrawable){      mBitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);      Canvas vectorCanvas = new Canvas(mBitmap);      drawable.setBounds(0, 0, vectorCanvas.getWidth(), vectorCanvas.getHeight());      drawable.draw(vectorCanvas);    }

重写onTouch

根据Touch 事件的左边获取 Bitmap 对应点的颜色。

需要注意的是如果 View 的宽和高参数是 wrap_content, MotionEvent 的点击的点一定在Bitmap 的坐标内。但是如果不是wrap_content，需要对坐标转换，利用矩阵Matrix 对点击点转换。

public boolean onTouch(View v, MotionEvent event) {    if (event.getAction() == MotionEvent.ACTION_DOWN && mBitmap != null) {        float scaleX = mBitmap.getWidth()*1.0f/v.getWidth();      float scaleY = mBitmap.getHeight()*1.0f/v.getHeight();      float[] touchPoint = new float[] { event.getX(), event.getY() };      Matrix matrix = new Matrix();      matrix.setScale(scaleX, scaleY);      matrix.mapPoints(touchPoint);      mSelectColor = mBitmap.getPixel((int) touchPoint[0], (int) touchPoint[1]);    }    return false;  }

完整的代码：

public class ColorPickerView extends android.support.v7.widget.AppCompatImageView implements View.OnTouchListener{  private Bitmap mBitmap;  private int mSelectColor = -1;  private int mIndex = -1;  private int[] mDrawableSelects;  private int[] mColorArray;  private OnColorSelectedListener mOnColorSelectedListener;  public ColorPickerView(Context context) {    this(context, null);  }  public ColorPickerView(Context context, @Nullable AttributeSet attrs) {    this(context, attrs, 0);  }  public ColorPickerView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    init(context, attrs, defStyleAttr);  }  void init(Context context, @Nullable AttributeSet attrs, int defStyleAttr){    Drawable drawable = getBackground();    if(drawable instanceof BitmapDrawable){      mBitmap = ((BitmapDrawable) drawable).getBitmap();    } else if(drawable instanceof VectorDrawable){      mBitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);      Canvas vectorCanvas = new Canvas(mBitmap);      drawable.setBounds(0, 0, vectorCanvas.getWidth(), vectorCanvas.getHeight());      drawable.draw(vectorCanvas);    }    TypedArray resTypeArray = context.obtainStyledAttributes(attrs, R.styleable.ColorPickerView);    int colorPickerArrayId = resTypeArray.getResourceId(R.styleable.ColorPickerView_cp_selected_drawable_array, 0);    resTypeArray.recycle();    if (colorPickerArrayId != 0) {      TypedArray typeArray = getResources().obtainTypedArray(colorPickerArrayId);      mDrawableSelects = new int[typeArray.length()];      for (int i = 0; i < typeArray.length(); i++) {        mDrawableSelects[i] = typeArray.getResourceId(i, 0);      }      typeArray.recycle();    }    setOnTouchListener(this);  }  @Override  public boolean onTouch(View v, MotionEvent event) {    if (event.getAction() == MotionEvent.ACTION_DOWN && mBitmap != null) {      if(event.getX() > v.getWidth() || event.getX() < 0){        return false;      }      if(event.getY() > v.getHeight() || event.getY() < 0){        return false;      }      float scaleX = mBitmap.getWidth()*1.0f/v.getWidth();      float scaleY = mBitmap.getHeight()*1.0f/v.getHeight();      float[] touchPoint = new float[] { event.getX(), event.getY() };      Matrix matrix = new Matrix();      matrix.setScale(scaleX, scaleY);      matrix.mapPoints(touchPoint);      mSelectColor = mBitmap.getPixel((int) touchPoint[0], (int) touchPoint[1]);      mIndex = getColorIndex(mSelectColor);      if(mDrawableSelects.length > 0 && mIndex >=0 && mIndex < mDrawableSelects.length) {        ((ImageView) v).setImageResource(mDrawableSelects[mIndex]);      }      if(mOnColorSelectedListener != null){        mOnColorSelectedListener.onColorSelected(mIndex, mSelectColor);      }    }    return false;  }  private int getColorIndex(int color){    for (int i = 0 ; i < mColorArray.length; i++){      if(color == mColorArray[i]){        return i;      }    }    return -1;  }  public void setSelectColorArray(int[] array) {    mColorArray = array;  }  public void setSelectDrawableIdArray(int[] idArray){    mDrawableSelects = idArray;  }  public int getIndex(){    return mIndex;  }  public int getSelectColor(){    return mSelectColor;  }  public void setOnColorSelectedListener(OnColorSelectedListener listener){    mOnColorSelectedListener = listener;  }  public interface OnColorSelectedListener{    void onColorSelected(int index , int color);  }}

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