特点
支持多行水印，支持自定义角度，支持自定义文字大小。
原理：
使用一个TextView 占据整个页面。在TextView基础上面打水印。
用法：
具体的view在
package cn.fulushan.watermark.view;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;
import android.support.annotation.IntRange;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import java.util.List;
/**
* Created by fulushan on 18/4/5.
*/
public class WaterMarkBg extends Drawable {
private Paint paint = new Paint();
private List<String> labels;
private Context context;
private int degress;//角度
private int fontSize;//字体大小 单位sp
/**
* 初始化构造
* @param context 上下文
* @param labels 水印文字列表 多行显示支持
* @param degress 水印角度
* @param fontSize 水印文字大小
*/
public WaterMarkBg(Context context,List<String> labels, int degress,int fontSize) {
this.labels = labels;
this.context = context;
this.degress = degress;
this.fontSize = fontSize;
}
@Override
public void draw(@NonNull Canvas canvas) {
int width = getBounds().right;
int height = getBounds().bottom;
canvas.drawColor(Color.parseColor("#40F3F5F9"));
paint.setColor(Color.parseColor("#50AEAEAE"));
paint.setAntiAlias(true);
paint.setTextSize(sp2px(context,fontSize));
canvas.save();
canvas.rotate(degress);
float textWidth = paint.measureText(labels.get(0));
int index = 0;
for (int positionY = height / 10; positionY <= height; positionY += height / 10+80) {
float fromX = -width + (index++ % 2) * textWidth;
for (float positionX = fromX; positionX < width; positionX += textWidth * 2) {
int spacing = 0;//间距
for(String label:labels){
canvas.drawText(label, positionX, positionY+spacing, paint);
spacing = spacing+50;
}
}
}
canvas.restore();
}
@Override
public void setAlpha(@IntRange(from = 0, to = 255) int alpha) {
}
@Override
public void setColorFilter(@Nullable ColorFilter colorFilter) {
}
@Override
public int getOpacity() {
return PixelFormat.UNKNOWN;
}
public static int sp2px(Context context, float spValue) {
final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;
return (int) (spValue * fontScale + 0.5f);
}
}
具体的用法
public class MainActivity extends AppCompatActivity {
private TextView bg_tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bg_tv = findViewById(R.id.bg_tv);
SimpleDateFormat createTimeSdf1 = new SimpleDateFormat("yyyy-MM-dd");
List<String> labels = new ArrayList<>();
labels.add("用户名：张三");
labels.add("日期："+ createTimeSdf1.format(new Date()));
labels.add("不可扩散");
bg_tv.setBackgroundDrawable(new WaterMarkBg(MainActivity.this,labels,-30,13));
}
}
效果图
github源码地址
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。
