android 自定义控件 自定义属性详细介绍

自定义控件在android中无处不见，自定义控件给了我们很大的方便。比如说，一个视图为imageview ，imagebutton ,textview 等诸多控件的组合，用的地方有很多，我们不可能每次都来写3个的组合，既浪费时间，效率又低。在这种情况下，我们就可以自定义一个view来替换他们，不仅提升了效率并且在xml中运用也是相当的美观。
一、控件自定义属性介绍
以下示例中代码均在values/attrs.xml 中定义，属性均可随意命名。
1. reference：参考某一资源ID。

示例：

<declare-styleable name = "名称"> 
<attr name = "background" format = "reference" /> 
<attr name = "src" format = "reference" /> 
</declare-styleable> 

2. color：颜色值。
示例： 

<declare-styleable name = "名称"> 
<attr name = "textColor" format = "color" /> 
</declare-styleable> 

3. boolean：布尔值。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "focusable" format = "boolean" /> 
</declare-styleable> 


4. dimension：尺寸值。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "layout_width" format = "dimension" /> 
</declare-styleable> 


5. float：浮点值。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "fromAlpha" format = "float" /> 
<attr name = "toAlpha" format = "float" /> 
</declare-styleable> 


6. integer：整型值。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "frameDuration" format="integer" /> 
<attr name = "framesCount" format="integer" /> 
</declare-styleable> 


7. string：字符串。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "text" format = "string" /> 
</declare-styleable> 


8. fraction：百分数。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name="名称"> 
<attr name = "pivotX" format = "fraction" /> 
<attr name = "pivotY" format = "fraction" /> 
</declare-styleable> 


9. enum：枚举值。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name="名称"> 
<attr name="orientation"> 
<enum name="horizontal" value="0" /> 
<enum name="vertical" value="1" /> 
</attr> 
</declare-styleable> 


10. flag：位或运算。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name="名称"> 
<attr name="windowSoftInputMode"> 
<flag name = "stateUnspecified" value = "0" /> 
<flag name = "stateUnchanged" value = "1" /> 
<flag name = "stateHidden" value = "2" /> 
<flag name = "stateAlwaysHidden" value = "3" /> 
</attr> 
</declare-styleable> 


11.多类型。 
示例： 
[java] 
复制代码 代码如下:
<declare-styleable name = "名称"> 
<attr name = "background" format = "reference|color" /> 
</declare-styleable>

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二、属性的使用以及自定义控件的实现

1、构思控件的组成元素，思考所需自定义的属性。
比如：我要做一个 <带阴影的按钮，按钮正下方有文字说明>（类似9宫格按钮）
新建values/attrs.xml 

<?xml version="1.0" encoding="utf-8"?> 
<resources> 
<declare-styleable name="custom_view"> 
<attr name="custom_id" format="integer" /> 
<attr name="src" format="reference" /> 
<attr name="background" format="reference" /> 
<attr name="text" format="string" /> 
<attr name="textColor" format="color" /> 
<attr name="textSize" format="dimension" /> 
</declare-styleable> 
</resources> 

以上，所定义为custom_view，custom_id为按钮id，src为按钮，background为阴影背景，text为按钮说明，textColor为字体颜色，textSize为字体大小。
2、怎么自定义控件呢，怎么使用这些属性呢？话不多说请看代码，CustomView ： 

package com.nanlus.custom; 
import com.nanlus.custom.R; 
import android.content.Context; 
import android.content.res.TypedArray; 
import android.graphics.Color; 
import android.graphics.drawable.Drawable; 
import android.util.AttributeSet; 
import android.view.Gravity; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.FrameLayout; 
import android.widget.ImageButton; 
import android.widget.ImageView; 
import android.widget.TextView; 
public class CustomView extends FrameLayout implements OnClickListener { 
private CustomListener customListener = null; 
private Drawable mSrc = null, mBackground = null; 
private String mText = ""; 
private int mTextColor = 0; 
private float mTextSize = 20; 
private int mCustomId = 0; 
private ImageView mBackgroundView = null; 
private ImageButton mButtonView = null; 
private TextView mTextView = null; 
private LayoutParams mParams = null; 
public CustomView(Context context) { 
super(context); 
} 
public CustomView(Context context, AttributeSet attrs) { 
super(context, attrs); 
TypedArray a = context.obtainStyledAttributes(attrs, 
R.styleable.custom_view); 
mSrc = a.getDrawable(R.styleable.custom_view_src); 
mBackground = a.getDrawable(R.styleable.custom_view_background); 
mText = a.getString(R.styleable.custom_view_text); 
mTextColor = a.getColor(R.styleable.custom_view_textColor, 
Color.WHITE); 
mTextSize = a.getDimension(R.styleable.custom_view_textSize, 20); 
mCustomId = a.getInt(R.styleable.custom_view_custom_id, 0); 
mTextView = new TextView(context); 
mTextView.setTextSize(mTextSize); 
mTextView.setTextColor(mTextColor); 
mTextView.setText(mText); 
mTextView.setGravity(Gravity.CENTER); 
mTextView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, 
LayoutParams.WRAP_CONTENT)); 
mButtonView = new ImageButton(context); 
mButtonView.setImageDrawable(mSrc); 
mButtonView.setBackgroundDrawable(null); 
mButtonView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, 
LayoutParams.WRAP_CONTENT)); 
mButtonView.setOnClickListener(this); 
mBackgroundView = new ImageView(context); 
mBackgroundView.setImageDrawable(mBackground); 
mBackgroundView.setLayoutParams(new LayoutParams( 
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 
addView(mBackgroundView); 
addView(mButtonView); 
addView(mTextView); 
this.setOnClickListener(this); 
a.recycle(); 
} 
@Override 
protected void onAttachedToWindow() { 
super.onAttachedToWindow(); 
mParams = (LayoutParams) mButtonView.getLayoutParams(); 
if (mParams != null) { 
mParams.gravity = Gravity.CENTER_HORIZONTAL | Gravity.TOP; 
mButtonView.setLayoutParams(mParams); 
} 
mParams = (LayoutParams) mBackgroundView.getLayoutParams(); 
if (mParams != null) { 
mParams.gravity = Gravity.CENTER_HORIZONTAL | Gravity.TOP; 
mBackgroundView.setLayoutParams(mParams); 
} 
mParams = (LayoutParams) mTextView.getLayoutParams(); 
if (mParams != null) { 
mParams.gravity = Gravity.CENTER_HORIZONTAL | Gravity.BOTTOM; 
mTextView.setLayoutParams(mParams); 
} 
} 
public void setCustomListener(CustomListener l) { 
customListener = l; 
} 
@Override 
public void onClick(View v) { 
if (customListener != null) { <pre name="code" class="plain">

customListener.onCuscomClick(v, mCustomId); } } public interface CustomListener { void onCuscomClick(View v, int custom_id); } }

代码很简单，就不多说，下面来看看我们的CustomView是怎么用的，请看： 3、自定义控件的使用 话不多说，请看代码，main.xml：  

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:nanlus="http://schemas.android.com/apk/res/com.nanlus.custom" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent" > 
<LinearLayout 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:layout_centerHorizontal="true" 
android:layout_centerVertical="true" 
android:orientation="horizontal" > 
<com.nanlus.custom.CustomView 
android:id="@+id/custom1" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:layout_weight="1" 
nanlus:background="@drawable/background" 
nanlus:custom_id="1" 
nanlus:src="@drawable/style_button" 
nanlus:text="按钮1" > 
</com.nanlus.custom.CustomView> 
</LinearLayout> 
</RelativeLayout>

在这里需要解释一下，
xmlns:nanlus="http://schemas.android.com/apk/res/com.nanlus.custom"
nanlus为在xml中的前缀，com.nanlus.custom为包名
4、在Activity中，直接上代码 

package com.nanlus.custom; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.ImageButton; 
import android.widget.ImageView; 
import android.widget.TextView; 
import android.widget.Toast; 
import com.nanlus.BaseActivity; 
import com.nanlus.custom.R; 
import com.nanlus.custom.CustomView.CustomListener; 
public class CustomActivity extends BaseActivity implements CustomListener { 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.main); 
((CustomView) this.findViewById(R.id.custom1)).setCustomListener(this); 
} 
@Override 
public void onCuscomClick(View v, int custom_id) { 
switch (custom_id) { 
case 1: 
Toast.makeText(this, "hello !!!", Toast.LENGTH_LONG).show(); 
break; 
default: 
break; 
} 
} 
}