一：如何自定义TextView实现滚动效果

1. 继承TextView基类
2. 重写构造方法
3. 修改isFocused()方法，获取焦点。

/*

 * Copyright (C) 2015 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

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

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.android.settings.utils;

import android.content.Context;

import android.util.AttributeSet;

import android.widget.TextView;

public class FocusedTextView extends TextView {

    public FocusedTextView(Context context) {

        super(context);

    }

    public FocusedTextView(Context context, AttributeSet attrs) {

        super(context, attrs);

    }

    public FocusedTextView(Context context, AttributeSet attrs, int defStyle) {

        super(context, attrs, defStyle);

    }

    public boolean isFocused() {

        return true;

    }

}

二：布局xml文件写法

主要设置如下两项:

android:singleLine="true" 单行显示

android:ellipsize="marquee"滚动

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="wrap_content"

    android:focusable="true"

    android:orientation="vertical" >

    <!--FocusedTextView的全路径名称,其他选项设置和TextView一样-->

    <com.android.settings.utils.FocusedTextView

        android:id="@+id/title"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:includeFontPadding="false"

        android:paddingLeft="@dimen/item_padding_x"

        android:singleLine="true"

        android:ellipsize="marquee"

        android:textColor="@drawable/app_text_color"

        android:textSize="@dimen/item_textsize" />

    <com.android.settings.utils.FocusedTextView

        android:id="@+id/summary"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:includeFontPadding="false"

        android:paddingLeft="@dimen/item_padding_x"

        android:singleLine="true"

        android:ellipsize="marquee"

        android:text="Summary"

        android:textColor="@drawable/app_text_color"

        android:textSize="@dimen/item_textsize" />

</LinearLayout>

三：总结

1. 继承基类TextView
2. 修改isFocused()方法
3. 设置TextView属性

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