package com.marshalchen.common.uimodule.titanic; import android.content.Context; import android.content.res.ColorStateList; import android.graphics.*; import android.graphics.drawable.Drawable; import android.util.AttributeSet; import android.widget.TextView; import com.marshalchen.common.uimodule.R; public class TitanicTextView extends TextView { public interface AnimationSetupCallback { public void onSetupAnimation(TitanicTextView titanicTextView); } // callback fired at first onSizeChanged private AnimationSetupCallback animationSetupCallback; // wave shader coordinates private float maskX, maskY; // if true, the shader will display the wave private boolean sinking; // true after the first onSizeChanged private boolean setUp; // shader containing a repeated wave private BitmapShader shader; // shader matrix private Matrix shaderMatrix; // wave drawable private Drawable wave; // (getHeight() - waveHeight) / 2 private float offsetY; public TitanicTextView(Context context) { super(context); init(); } public TitanicTextView(Context context, AttributeSet attrs) { super(context, attrs); init(); } public TitanicTextView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(); } private void init() { shaderMatrix = new Matrix(); } public AnimationSetupCallback getAnimationSetupCallback() { return animationSetupCallback; } public void setAnimationSetupCallback(AnimationSetupCallback animationSetupCallback) { this.animationSetupCallback = animationSetupCallback; } public float getMaskX() { return maskX; } public void setMaskX(float maskX) { this.maskX = maskX; invalidate(); } public float getMaskY() { return maskY; } public void setMaskY(float maskY) { this.maskY = maskY; invalidate(); } public boolean isSinking() { return sinking; } public void setSinking(boolean sinking) { this.sinking = sinking; } public boolean isSetUp() { return setUp; } @Override public void setTextColor(int color) { super.setTextColor(color); createShader(); } @Override public void setTextColor(ColorStateList colors) { super.setTextColor(colors); createShader(); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); createShader(); if (!setUp) { setUp = true; if (animationSetupCallback != null) { animationSetupCallback.onSetupAnimation(TitanicTextView.this); } } } /** * Create the shader * draw the wave with current color for a background * repeat the bitmap horizontally, and clamp colors vertically */ private void createShader() { if (wave == null) { wave = getResources().getDrawable(R.drawable.titanic_wave_black); } int waveW = wave.getIntrinsicWidth(); int waveH = wave.getIntrinsicHeight(); Bitmap b = Bitmap.createBitmap(waveW, waveH, Bitmap.Config.ARGB_8888); Canvas c = new Canvas(b); c.drawColor(getCurrentTextColor()); wave.setBounds(0, 0, waveW, waveH); wave.draw(c); shader = new BitmapShader(b, Shader.TileMode.REPEAT, Shader.TileMode.CLAMP); getPaint().setShader(shader); offsetY = (getHeight() - waveH) / 2; } @Override protected void onDraw(Canvas canvas) { // modify text paint shader according to sinking state if (sinking && shader != null) { // first call after sinking, assign it to our paint if (getPaint().getShader() == null) { getPaint().setShader(shader); } // translate shader accordingly to maskX maskY positions // maskY is affected by the offset to vertically center the wave shaderMatrix.setTranslate(maskX, maskY + offsetY); // assign matrix to invalidate the shader shader.setLocalMatrix(shaderMatrix); } else { getPaint().setShader(null); } super.onDraw(canvas); } }