Android Textview實現文字顏色漸變效果

時間 2019-12-12

標籤 android textview 實現文字顏色漸變效果欄目 Android 简体版

原文原文鏈接

最近作應用的時候遇到一個需求，一行文字的顏色須要一個漸變效果android

如上全部從左到有逐漸變化，本身寫了一個demo實現上述效果canvas

package com.huwei.example.test;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Shader;
import android.util.AttributeSet;
import android.widget.TextView;
 
public class MyTextView extends TextView {
 
    private LinearGradient mLinearGradient;
    private Paint mPaint;
    private int mViewWidth = 0;
    private Rect mTextBound = new Rect();
    public MyTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
 
    @Override
    protected void onDraw(Canvas canvas) {
        mViewWidth = getMeasuredWidth();
        mPaint = getPaint();
        String mTipText = getText().toString();
        mPaint.getTextBounds(mTipText, 0, mTipText.length(), mTextBound);
        mLinearGradient = new LinearGradient(0, 0, mViewWidth, 0,
                new int[] {  0xFF429321, 0xFFB4EC51 },
                null, Shader.TileMode.REPEAT);
        mPaint.setShader(mLinearGradient);
        canvas.drawText(mTipText, getMeasuredWidth() / 2 - mTextBound.width() / 2, getMeasuredHeight() / 2 +   mTextBound.height()/2, mPaint);
    }
 
}