Go语言视频零基础入门到精通

aopre8

       seekarPreference控件，保存的Value为数字值，直接可以在preferences.xml文件中使用无需其他代码。

        下面是控件使用到得标准Android属性
        android:dialogMessage 显示对话框中的文本信息
        android:text  在选择进度条后，显示的文本信息
        android:max SeekBar的最大值

java代码： /* The following code was written by Matthew Wiggins

* and is released under the APACHE 2.0 license

*

* http://www.apache.org/licenses/LICENSE-2.0

*/

package eoe.demo;



import android.content.Context;

import android.util.AttributeSet;

import android.view.Gravity;

import android.view.View;

import android.view.ViewGroup;

import android.preference.DialogPreference;

import android.widget.SeekBar;

import android.widget.TextView;

import android.widget.LinearLayout;





public class SeekBarPreference extends DialogPreference implements SeekBar.OnSeekBarChangeListener

{

private static final String androidns="http://schemas.android.com/apk/res/android";



private SeekBar mSeekBar;

private TextView mSplashText,mValueText;

private Context mContext;



private String mDialogMessage, mSuffix;

private int mDefault, mMax, mValue = 0;



public SeekBarPreference(Context context, AttributeSet attrs) {

super(context,attrs);

mContext = context;



mDialogMessage = attrs.getAttributeValue(androidns,"dialogMessage");

mSuffix = attrs.getAttributeValue(androidns,"text");

mDefault = attrs.getAttributeIntValue(androidns,"defaultValue", 0);

mMax = attrs.getAttributeIntValue(androidns,"max", 100);



}

@Override

protected View onCreateDialogView() {

LinearLayout.LayoutParams params;

LinearLayout layout = new LinearLayout(mContext);

layout.setOrientation(LinearLayout.VERTICAL);

layout.setPadding(6,6,6,6);



mSplashText = new TextView(mContext);

if (mDialogMessage != null)

mSplashText.setText(mDialogMessage);

layout.addView(mSplashText);



mValueText = new TextView(mContext);

mValueText.setGravity(Gravity.CENTER_HORIZONTAL);

mValueText.setTextSize(32);

params = new LinearLayout.LayoutParams(

LinearLayout.LayoutParams.FILL_PARENT,

LinearLayout.LayoutParams.WRAP_CONTENT);

layout.addView(mValueText, params);



mSeekBar = new SeekBar(mContext);

mSeekBar.setOnSeekBarChangeListener(this);

layout.addView(mSeekBar, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT));



if (shouldPersist())

mValue = getPersistedInt(mDefault);



mSeekBar.setMax(mMax);

mSeekBar.setProgress(mValue);

return layout;

}

@Override

protected void onBindDialogView(View v) {

super.onBindDialogView(v);

mSeekBar.setMax(mMax);

mSeekBar.setProgress(mValue);

}

@Override

protected void onSetInitialValue(boolean restore, Object defaultValue)

{

super.onSetInitialValue(restore, defaultValue);

if (restore)

mValue = shouldPersist() ? getPersistedInt(mDefault) : 0;

else

mValue = (Integer)defaultValue;

}



public void onProgressChanged(SeekBar seek, int value, boolean fromTouch)

{

String t = String.valueOf(value);

mValueText.setText(mSuffix == null ? t : t.concat(mSuffix));

if (shouldPersist())

persistInt(value);

callChangeListener(new Integer(value));

}

public void onStartTrackingTouch(SeekBar seek) {}

public void onStopTrackingTouch(SeekBar seek) {}



public void setMax(int max) { mMax = max; }

public int getMax() { return mMax; }



public void setProgress(int progress) {

mValue = progress;

if (mSeekBar != null)

mSeekBar.setProgress(progress);

}

public int getProgress() { return mValue; }

}
下面是在XML layout的例子

java代码： <eoe.demo.SeekBarPreference android:key="duration"

android:title="Duration of something"

android:summary="How long something will last"

android:dialogMessage="Something duration"

android:defaultValue="5"

android:text=" minutes"

android:max="60"

/>