Android 如何将自定义视图添加到布局？
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How to add custom view to the layout?
提问by AnasBakez
I have a GraphicsViewclass that extends from the Viewclass and I want to add this GraphicsViewclass to the main layout in my project. How can I do that?
我有一个GraphicsView从类扩展的View类，我想将这个GraphicsView类添加到我项目的主布局中。我怎样才能做到这一点？
static public class GraphicsView extends View {
public GraphicsView(Context context) {
super(context);
}
@Override
protected void onDraw(Canvas canvas) {
// Drawing commands go here
Path rect = new Path();
rect.addRect(100, 100, 250, 50, Direction.CW);
Paint cPaint = new Paint();
cPaint.setColor(Color.LTGRAY);
canvas.drawPath(rect, cPaint);
}
}
and my main.xml:
和我的main.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linnnnlayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<TextView
android:id="@+id/Customfont"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<View
android:id="@+id/view"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
回答by Lalit Poptani
You need to give complete path of your class that extends View,
您需要提供扩展视图的类的完整路径，
<com.blah.blah.GraphicsView
android:id="@+id/view"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
回答by Sver
If I remember correctly, you need to provide more constructors to use view from xml file (add it to xml file like "Me and We" suggested).
如果我没记错的话，您需要提供更多构造函数来使用 xml 文件中的视图（建议将其添加到 xml 文件中，例如“我和我们”）。
public GraphicsView(Context context) {
super(context);
}
public GraphicsView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public GraphicsView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
Update: fixed code.
更新：固定代码。
回答by AnasBakez
i finaly got it here is the code the XML code
我最终得到了它是代码 XML 代码
<com.customfonts.namespace.BreakDownBar
android:id="@+id/gview"
android:layout_width="fill_parent"
android:layout_height="20dip"
android:layout_marginLeft="10dip"
android:layout_marginRight="10dip"
android:background="@color/BreakDownBarBack"/>
and the class
和班级
package com.customfonts.namespace;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Path.Direction;
import android.util.AttributeSet;
import android.view.View;
public class BreakDownBar extends View {
public BreakDownBar(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onDraw(Canvas canvas) {
//Draw rectangle;
Path rect = new Path();
rect.addRect(0, 0,250, 150,Direction.CW);
Paint cpaint = new Paint();
cpaint.setColor(Color.GREEN);
canvas.drawPath(rect, cpaint);
}
}
回答by thepoosh
you need to do this:
你需要这样做：
LinearLayout v = (LinearView) findViewById(R.id.linnnnlayout);
GraphicsView myView = new myGraphicsView(this);
v.addView(myView);
回答by Luksprog
Because your custom Viewis an inner class in your Activitythe java compiler will output the name ActivityName$GraphicsViewfor that class. You can't use that name directly as the Viewname in the xml layout because of the $character but you can do it like this:
因为您的自定义View是ActivityJava 编译器中的内部类，所以将输出ActivityName$GraphicsView该类的名称。View由于$字符的原因，您不能直接使用该名称作为xml 布局中的名称，但您可以这样做：
<view
class="com.package.here.ActivityName$GraphicsView"
android:id="@+id/view"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
where ActivityNameis the name of the activity where your GraphicsViewclass is declared.
where是声明ActivityName您的GraphicsView类的活动的名称。
回答by M.Praveen Kumar
This is working for me and add the view in XML with full path and try giving wrapcontent for height and width.
这对我有用，并在带有完整路径的 XML 中添加视图，并尝试为高度和宽度提供 wrapcontent。
public class RectangleView extends View {
public RectangleView(Context context) {
super(context);
}
public RectangleView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public RectangleView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Paint paint = new Paint();
paint.setColor(Color.GRAY);
canvas.drawColor(Color.BLUE);
canvas.drawRect(10,10,50,50, paint);
}
}
回答by Krishnakant Dalal
public class MainActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
LinearLayout v = (LinearLayout) findViewById(R.id.linearLayout);
MyGraphics myView = new MyGraphics(this);
v.addView(myView);
}
}
public class MyGraphics extends View {
public MyGraphics(Context context) {
super(context);
}
@Override
protected void onDraw(Canvas canvas) {
// Drawing commands go here
Path rect = new Path();
rect.addRect(100, 100, 250, 50, Direction.CW);
Paint cPaint = new Paint();
cPaint.setColor(Color.LTGRAY);
canvas.drawPath(rect, cPaint);
}
}
XML:
XML：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:id="@+id/linearLayout">
<TextView
android:id="@+id/Customfont"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
</LinearLayout>
