Android自定义视图不起作用
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【中文标题】Android自定义视图不起作用【英文标题】:Android Custom View Not Working 【发布时间】:2015-02-23 23:38:45 【问题描述】:我正在尝试绘制折线图。 Accualy 我成功了,但是当我想在活动中显示此视图时,我遇到了错误(无法解释的错误),我正在使用 android studio 和所有代码。
我的活动从不加载。抛出错误。
查看类;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.view.Display;
import android.view.View;
import android.view.WindowManager;
import android.widget.Toast;
import java.security.PublicKey;
public class DwarView extends View
public int[]yuzde; //im getting some values
Paint paint = new Paint();
Paint paint2 = new Paint(); //my paints for drawing
Paint paint3 = new Paint();
public DwarView(Context context)
super(context);
paint.setStrokeWidth(6f);
paint.setColor(Color.BLACK);
paint2.setStrokeWidth(3f);
paint2.setColor(Color.BLUE);
paint3.setColor(Color.LTGRAY);
paint3.setStrokeWidth(2f);
private float Hesapla(int Yuzde)
float sonuc;
sonuc = 500-(500*Yuzde)/100;
return sonuc;
@Override
public void onDraw(Canvas canvas)
super.onDraw(canvas);
WindowManager wm = (WindowManager)getContext().getSystemService(Context.WINDOW_SERVICE);
Display ekran = wm.getDefaultDisplay();
Point olcu = new Point();
ekran.getSize(olcu);
int genislik = olcu.x;
int yukseklik = olcu.y;
int row = olcu.x/12;
canvas.drawLine(row,0,row,500,paint3);
canvas.drawLine(row*2,0,row*2,500,paint3);
canvas.drawLine(row*3,0,row*3,500,paint3);
canvas.drawLine(row*4,0,row*4,500,paint3);
canvas.drawLine(row*5,0,row*5,500,paint3);
canvas.drawLine(row*6,0,row*6,500,paint3);
canvas.drawLine(row*7,0,row*7,500,paint3);
canvas.drawLine(row*8,0,row*8,500,paint3);
canvas.drawLine(row*9,0,row*9,500,paint3);
canvas.drawLine(row*10,0,row*10,500,paint3);
canvas.drawLine(row*11,0,row*11,500,paint3);
canvas.drawLine(0,100,genislik,100,paint3);
canvas.drawLine(0,200,genislik,200,paint3);
canvas.drawLine(0,300,genislik,300,paint3);
canvas.drawLine(0,400,genislik,400,paint3);
canvas.drawLine(0,500,row,Hesapla(yuzde[0]),paint2);
canvas.drawLine(row,Hesapla(yuzde[0]),row*2,Hesapla(yuzde[1]),paint2);
canvas.drawLine(row*2,Hesapla(yuzde[1]),row*3,Hesapla(yuzde[2]),paint2);
canvas.drawLine(row*3,Hesapla(yuzde[2]),row*4,Hesapla(yuzde[3]),paint2);
canvas.drawLine(row*4,Hesapla(yuzde[3]),row*5,Hesapla(yuzde[4]),paint2);
canvas.drawLine(row*5,Hesapla(yuzde[4]),row*6,Hesapla(yuzde[5]),paint2);
canvas.drawLine(row*6,Hesapla(yuzde[5]),row*7,Hesapla(yuzde[6]),paint2);
canvas.drawLine(row*7,Hesapla(yuzde[6]),row*8,Hesapla(yuzde[7]),paint2);
canvas.drawLine(row*8,Hesapla(yuzde[7]),row*9,Hesapla(yuzde[8]),paint2);
canvas.drawLine(row*9,Hesapla(yuzde[8]),row*10,Hesapla(yuzde[9]),paint2);
canvas.drawLine(row*10,Hesapla(yuzde[9]),row*11,Hesapla(yuzde[10]),paint2);
canvas.drawLine(row*11,Hesapla(yuzde[10]),row*12,Hesapla(yuzde[11]),paint2);
canvas.drawLine(0,500,genislik,500,paint);
主要活动;
import android.graphics.Color;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends ActionBarActivity
DwarView drawView;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
drawView = new DwarView(this);
drawView.setBackgroundColor(Color.WHITE);
drawView.yuzde = new int[] 10,50,60,30,70,100,50,80,90,10,30,50;
setContentView(R.layout.activity_main);
主要活动设计 Xml;
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_
android:layout_ android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">
<com.adjans.huskerr.acharttest.DwarView
android:layout_
android:layout_/>
</RelativeLayout>
AndroidManifest 文件;
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.adjans.huskerr.acharttest" >
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
LogCat 日志;
24 11:48:18.236 23544-23544/com.adjans.huskerr.acharttest D/dalvikvm﹕ VFY: replacing opcode 0x6f at 0x0000
02-24 11:48:18.236 23544-23544/com.adjans.huskerr.acharttest I/dalvikvm﹕ Could not find method android.support.v7.internal.widget.ActionBarOverlayLayout.stopNestedScroll, referenced from method android.support.v7.internal.widget.ActionBarOverlayLayout.setHideOnContentScrollEnabled
02-24 11:48:18.236 23544-23544/com.adjans.huskerr.acharttest W/dalvikvm﹕ VFY: unable to resolve virtual method 9082: Landroid/support/v7/internal/widget/ActionBarOverlayLayout;.stopNestedScroll ()V
02-24 11:48:18.236 23544-23544/com.adjans.huskerr.acharttest D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x000e
02-24 11:48:18.241 23544-23544/com.adjans.huskerr.acharttest I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.internal.widget.TintTypedArray.getChangingConfigurations
02-24 11:48:18.241 23544-23544/com.adjans.huskerr.acharttest W/dalvikvm﹕ VFY: unable to resolve virtual method 366: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
02-24 11:48:18.241 23544-23544/com.adjans.huskerr.acharttest D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
02-24 11:48:18.246 23544-23544/com.adjans.huskerr.acharttest I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.internal.widget.TintTypedArray.getType
02-24 11:48:18.246 23544-23544/com.adjans.huskerr.acharttest W/dalvikvm﹕ VFY: unable to resolve virtual method 388: Landroid/content/res/TypedArray;.getType (I)I
02-24 11:48:18.246 23544-23544/com.adjans.huskerr.acharttest D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
02-24 11:48:18.276 23544-23544/com.adjans.huskerr.acharttest D/AndroidRuntime﹕ Shutting down VM
02-24 11:48:18.276 23544-23544/com.adjans.huskerr.acharttest W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x418f5c08)
02-24 11:48:18.286 23544-23544/com.adjans.huskerr.acharttest E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.adjans.huskerr.acharttest, PID: 23544
java.lang.RuntimeException: Unable to start activity ComponentInfocom.adjans.huskerr.acharttest/com.adjans.huskerr.acharttest.MainActivity: android.view.InflateException: Binary XML file line #7: Error inflating class com.adjans.huskerr.acharttest.DwarView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2436)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2495)
at android.app.ActivityThread.access$900(ActivityThread.java:170)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1304)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:146)
at android.app.ActivityThread.main(ActivityThread.java:5635)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1291)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1107)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.view.InflateException: Binary XML file line #7: Error inflating class com.adjans.huskerr.acharttest.DwarView
at android.view.LayoutInflater.createView(LayoutInflater.java:609)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:702)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:761)
at android.view.LayoutInflater.inflate(LayoutInflater.java:498)
at android.view.LayoutInflater.inflate(LayoutInflater.java:398)
at android.view.LayoutInflater.inflate(LayoutInflater.java:354)
at android.support.v7.app.ActionBarActivityDelegateBase.setContentView(ActionBarActivityDelegateBase.java:228)
at android.support.v7.app.ActionBarActivity.setContentView(ActionBarActivity.java:102)
at com.adjans.huskerr.acharttest.MainActivity.onCreate(MainActivity.java:20)
at android.app.Activity.performCreate(Activity.java:5585)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1093)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2400)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2495)
at android.app.ActivityThread.access$900(ActivityThread.java:170)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1304)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:146)
at android.app.ActivityThread.main(ActivityThread.java:5635)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1291)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1107)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NoSuchMethodException: <init> [class android.content.Context, interface android.util.AttributeSet]
at java.lang.Class.getConstructorOrMethod(Class.java:472)
at java.lang.Class.getConstructor(Class.java:446)
at android.view.LayoutInflater.createView(LayoutInflater.java:574)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:702)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:761)
at android.view.LayoutInflater.inflate(LayoutInflater.java:498)
at android.view.LayoutInflater.inflate(LayoutInflater.java:398)
at android.view.LayoutInflater.inflate(LayoutInflater.java:354)
at android.support.v7.app.ActionBarActivityDelegateBase.setContentView(ActionBarActivityDelegateBase.java:228)
at android.support.v7.app.ActionBarActivity.setContentView(ActionBarActivity.java:102)
at com.adjans.huskerr.acharttest.MainActivity.onCreate(MainActivity.java:20)
at android.app.Activity.performCreate(Activity.java:5585)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1093)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2400)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2495)
at android.app.ActivityThread.access$900(ActivityThread.java:170)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1304)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:146)
at android.app.ActivityThread.main(ActivityThread.java:5635)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1291)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1107)
at dalvik.system.NativeStart.main(Native Method)
【问题讨论】:
你在使用 achartengine 吗? 不只是我的包名。 能否请您附上您遇到的错误? Ide 没有给我任何错误,但我用 logcat 日志更新了我的问题。 【参考方案1】:关注this guide。 你还没有实现构造函数。为了能够在 xml 中使用视图,您应该从 View 中实现 2 个其他构造函数:
public DwarView(Context context, AttributeSet attrs)
super(context, attrs);
public DwarView(Context context, AttributeSet attrs, int defStyle)
super(context, attrs, defStyle);
将此构造函数添加到您的 customView 类。
还有Read this
【讨论】:
在 xml 中为您的视图提供一个 id 并为您的视图提供 findViewById【参考方案2】:要在 xml 中使用自定义视图,您必须声明一个带有两个参数的构造函数,如您获得的异常中所指定:
Caused by: java.lang.NoSuchMethodException: <init> [class android.content.Context, interface android.util.AttributeSet]
像这样:
public DwarView(Context context,android.util.AttributeSet attrs)
super(context,attrs);
...
【讨论】:
我要写什么第二个变量? drawView = new DwarView(这个,这里?); 单参数构造函数很好,你可以在从代码中实例化视图时使用它。两参数构造函数旨在供 LayoutInflater 用于自动创建视图。以上是关于Android自定义视图不起作用的主要内容,如果未能解决你的问题,请参考以下文章