Android怎樣實現左上角傾斜的標簽效果

這篇文章主要介紹Android怎樣實現左上角傾斜的標簽效果，文中介紹的非常詳細，具有一定的參考價值，感興趣的小伙伴們一定要看完！

實現的思路大致如下圖：

主頁面的布局結構如下：

<?xml version="1.0" encoding="utf-8"?><androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:app="http://schemas.android.com/apk/res-auto"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:background="#fff"  android:layout_height="match_parent"  tools:context=".MainActivity">  <RelativeLayout    android:layout_width="300dp"    android:layout_height="200dp"    android:background="#fff"    app:layout_constraintBottom_toBottomOf="parent"    app:layout_constraintLeft_toLeftOf="parent"    app:layout_constraintRight_toRightOf="parent"    app:layout_constraintTop_toTopOf="parent" >    <RelativeLayout      android:layout_width="match_parent"      android:layout_height="match_parent"      android:layout_margin="5dp"      android:background="#33B7F3"      android:elevation="2dp"></RelativeLayout>    <com.zc.labeldemo.LabelView      android:id="@+id/labelView"      android:layout_alignParentTop="true"      android:layout_width="75dp"      android:elevation="3dp"      android:layout_height="75dp"/>  </RelativeLayout></androidx.constraintlayout.widget.ConstraintLayout>

繪制傾斜標簽的代碼如下：

package com.zc.labeldemo;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Path;import android.util.AttributeSet;import android.view.View;import androidx.annotation.Nullable;/** * @author wenchao * @version 1.0.1 * @className LabelView * @date 2019/9/20 * @description */public class LabelView extends View {  /**   * 畫筆   */  private Paint paint;  /**   * Path   */  private Path path;  /**   * View寬度   */  private float width;  /**   * View高度   */  private float height;  /**   * 標簽背景寬度   */  private float labelWidth;  /**   * 標簽折疊區域寬度   */  private float pointWidth;  /**   * 標簽折疊區域高度   */  private float pointHeight;  /**   * 標簽背景顏色   */  private int labelColor;  /**   * 標簽折疊區域背景顏色   */  private int pointColor;  /**   * 中心點x坐標   */  private float centerX;  /**   * 中心點y坐標   */  private float centerY;  /**   * 標簽文字內容   */  private String text;  /**   * 標簽文字顏色   */  private int textColor;  public LabelView(Context context) {    super(context);  }  public LabelView(Context context, @Nullable AttributeSet attrs) {    super(context, attrs);    init();  }  private void init() {    labelWidth = 120;    pointWidth = 10;    pointHeight = 17;    paint = new Paint();    path = new Path();    paint.setAntiAlias(true);    paint.setStrokeWidth(10);    setBackgroundColor(Color.TRANSPARENT);    labelColor = Color.parseColor("#EA6724");    pointColor = Color.parseColor("#C43200");    text = "測試內容";    textColor = Color.WHITE;  }  @Override  protected void onSizeChanged(int w, int h, int oldw, int oldh) {    super.onSizeChanged(w, h, oldw, oldh);    width = w;    height = h;    centerX = w/2;    centerY = h/2;  }  @Override  public void draw(Canvas canvas) {    super.draw(canvas);    //畫標簽區域背景上邊的折疊區域（小三角區域）    path.reset();    path.moveTo(width-pointWidth,0);    path.lineTo(width,pointHeight);    path.lineTo(width-pointWidth-26,pointHeight);    path.close();    paint.setColor(pointColor);    canvas.drawPath(path,paint);    //畫標簽背景區域下邊的折疊區域    path.reset();    path.moveTo(0,height-pointWidth);    path.lineTo(pointHeight,height);    path.lineTo(pointHeight,height-pointWidth-26);    path.close();    paint.setColor(pointColor);    canvas.drawPath(path,paint);    //畫標簽背景區域    path.reset();    paint.setColor(labelColor);    paint.setStyle(Paint.Style.FILL);    path.moveTo(width-labelWidth-pointWidth,0);    path.lineTo(width-pointWidth,0);    path.lineTo(0,height-pointWidth);    path.lineTo(0,height-labelWidth-pointWidth);    canvas.drawPath(path,paint);    //畫文字 逆時針選擇45度    canvas.rotate(-45,centerX,centerY);    //文字中心點橫坐標    float textX = width / 2;    //文字中心點縱坐標    float textY = (height-pointWidth-(labelWidth / 2f)) / 2f;    paint.setColor(textColor);    paint.setStyle(Paint.Style.FILL);    paint.setTextSize(38);    //設置文字居中繪制    paint.setTextAlign(Paint.Align.CENTER);    canvas.drawText(text,textX,textY,paint);  }}

以上是“Android怎樣實現左上角傾斜的標簽效果”這篇文章的所有內容，感謝各位的閱讀！希望分享的內容對大家有幫助，更多相關知識，歡迎關注億速云行業資訊頻道！