API Demos 2.2 研读笔记（5）——Window Feature

Android允许对手机屏幕的特征进行客户化，例如，客户化标题栏。如果我们想要对某一特征进行客户化，首先就要通过Window.requestFeature (int featureId) 方法进行申请。一旦申请了就不能去掉这个特征了。

Android事先为可能被客户化的特征定义了常量。

int	DEFAULT_FEATURES	The default features enabled
int	FEATURE_CONTEXT_MENU	Flag for the context menu.
int	FEATURE_CUSTOM_TITLE	Flag for custom title.
int	FEATURE_INDETERMINATE_PROGRESS	Flag for indeterminate progress
int	FEATURE_LEFT_ICON	Flag for having an icon on the left side of the title bar
int	FEATURE_NO_TITLE	Flag for the "no title" feature, turning off the title at the top of the screen.
int	FEATURE_OPTIONS_PANEL	Flag for the "options panel" feature.
int	FEATURE_PROGRESS	Flag for the progress indicator feature
int	FEATURE_RIGHT_ICON	Flag for having an icon on the right side of the title bar

下面以API Demo中Custom Title为例加以说明。

1. 首先创建客户化的title。

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/screen"    android:layout_width="match_parent" android:layout_height="match_parent"    android:orientation="vertical">    <TextView android:id="@+id/left_text"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentLeft="true"        android:text="@string/custom_title_left" />    <TextView android:id="@+id/right_text"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentRight="true"        android:text="@string/custom_title_right" /></RelativeLayout>

2. 在CustomTitle.java中将客户化的title应用到activity中。

package com.example.android.apis.app;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.Window;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import com.example.android.apis.R;public class CustomTitle extends Activity {    @Overrideprotected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);        setContentView(R.layout.custom_title);        getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.custom_title_1);                final TextView leftText = (TextView) findViewById(R.id.left_text);        final TextView rightText = (TextView) findViewById(R.id.right_text);        final EditText leftTextEdit = (EditText) findViewById(R.id.left_text_edit);        final EditText rightTextEdit = (EditText) findViewById(R.id.right_text_edit);        Button leftButton = (Button) findViewById(R.id.left_text_button);        Button rightButton = (Button) findViewById(R.id.right_text_button);                leftButton.setOnClickListener(new OnClickListener() {            public void onClick(View v) {                leftText.setText(leftTextEdit.getText());            }        });        rightButton.setOnClickListener(new OnClickListener() {            public void onClick(View v) {                rightText.setText(rightTextEdit.getText());            }        });    }}

先在setContentView之前调用requestWindowFeature(Window.FEATURE_CUSTOM_TITLE)，申请对标题进行客户化。然后调用getWindow().setFeatureInt将新的title应用到activity上。

客户化window feature时需要注意：

1. 要在setContentView之前调用requestFeature。由于requestWindowFeature = getWindow().requestFeature，所以调用requestWindowFeature 也可。

2. 不能将其他title相关feature与FEATURE_CUSTOM_TITLE一起使用。

更多相关文章

随机推荐