1、Button 是什么?

简单:按钮组件
官方:Button是一种常见的组件,点击可以触发对应的操作,通常由文本或图标组成,也可以由图标和文本共同组成。

2、普通按钮

HarmonyOS — Button按钮_HarmonyOS

<Button
    ohos:width="150vp"
    ohos:height="50vp"
    ohos:text_size="27fp"
    ohos:text="button"
    ohos:background_element="$graphic:color_blue_element"
    ohos:left_margin="15vp"
    ohos:bottom_margin="15vp"
    ohos:right_padding="8vp"
    ohos:left_padding="8vp"
/>

color_blue_element.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="rectangle">
    <solid
        ohos:color="#007CFD"/>
</shape>

3、椭圆按钮

HarmonyOS — Button按钮_Button组件_02

<Button
    ohos:width="150vp"
    ohos:height="50vp"
    ohos:text_size="27fp"
    ohos:text="button"
    ohos:background_element="$graphic:oval_button_element"
    ohos:left_margin="15vp"
    ohos:bottom_margin="15vp"
    ohos:right_padding="8vp"
    ohos:left_padding="8vp"
    ohos:element_left="$media:ic_btn_reload"
/>

oval_button_element.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="oval">
    <solid
        ohos:color="#007CFD"/>
</shape>

4、Button 响应事件

按钮的重要作用是当用户单击按钮时,会执行相应的操作或者界面出现相应的变化。实际上用户点击按钮时,Button对象将收到一个点击事件。开发者可以自定义响应点击事件的方法。例如,通过创建一个Component.ClickedListener对象,然后通过调用setClickedListener将其分配给按钮。

Button button = (Button) findComponentById(ResourceTable.Id_button);
// 为按钮设置点击事件回调
button.setClickedListener(new Component.ClickedListener() {
    @Override
    public void onClick(Component component) {
        // 此处添加点击按钮后的事件处理逻辑
    }
}); 

5、实战:拨号盘的UI界面

HarmonyOS — Button按钮_按钮_03

<?xml version="1.0" encoding="utf-8"?>
<DirectionalLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:width="match_parent"
    ohos:height="match_parent"
    ohos:background_element="$graphic:color_light_gray_element"
    ohos:orientation="vertical">
    <Text
        ohos:width="match_content"
        ohos:height="match_content"
        ohos:text_size="20fp"
        ohos:text="0123456789"
        ohos:background_element="$graphic:green_text_element"
        ohos:text_alignment="center"
        ohos:layout_alignment="horizontal_center"
    />
    <DirectionalLayout
        ohos:width="match_parent"
        ohos:height="match_content"
        ohos:alignment="horizontal_center"
        ohos:orientation="horizontal"
        ohos:top_margin="5vp"
        ohos:bottom_margin="5vp">
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="1"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="2"
            ohos:left_margin="5vp"
            ohos:right_margin="5vp"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="3"
            ohos:text_alignment="center"
        />
    </DirectionalLayout>
    <DirectionalLayout
        ohos:width="match_parent"
        ohos:height="match_content"
        ohos:alignment="horizontal_center"
        ohos:orientation="horizontal"
        ohos:bottom_margin="5vp">
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="4"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:left_margin="5vp"
            ohos:right_margin="5vp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="5"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="6"
            ohos:text_alignment="center"
        />
    </DirectionalLayout>
    <DirectionalLayout
        ohos:width="match_parent"
        ohos:height="match_content"
        ohos:alignment="horizontal_center"
        ohos:orientation="horizontal"
        ohos:bottom_margin="5vp">
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="7"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:left_margin="5vp"
            ohos:right_margin="5vp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="8"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="9"
            ohos:text_alignment="center"
        />
    </DirectionalLayout>
    <DirectionalLayout
        ohos:width="match_parent"
        ohos:height="match_content"
        ohos:alignment="horizontal_center"
        ohos:orientation="horizontal"
        ohos:bottom_margin="5vp">
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="*"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:left_margin="5vp"
            ohos:right_margin="5vp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="0"
            ohos:text_alignment="center"
        />
        <Button
            ohos:width="40vp"
            ohos:height="40vp"
            ohos:text_size="15fp"
            ohos:background_element="$graphic:green_circle_button_element"
            ohos:text="#"
            ohos:text_alignment="center"
        />
    </DirectionalLayout>
    <Button
        ohos:width="match_content"
        ohos:height="match_content"
        ohos:text_size="15fp"
        ohos:text="CALL"
        ohos:background_element="$graphic:green_capsule_button_element"
        ohos:bottom_margin="5vp"
        ohos:text_alignment="center"
        ohos:layout_alignment="horizontal_center"
        ohos:left_padding="10vp"
        ohos:right_padding="10vp"
        ohos:top_padding="2vp"
        ohos:bottom_padding="2vp"
    />
</DirectionalLayout>

color_light_gray_element.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="rectangle">
    <solid
        ohos:color="#EDEDED"/>
</shape>
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="rectangle">
    <corners
        ohos:radius="20"/>
    <stroke
        ohos:width="2"
        ohos:color="#006E00"/>
    <solid
        ohos:color="#EDEDED"/>
</shape>
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="oval">
    <stroke
        ohos:width="5"
        ohos:color="#006E00"/>
    <solid
        ohos:color="#EDEDED"/>
</shape>
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:shape="rectangle">
    <corners
        ohos:radius="100"/>
    <solid
        ohos:color="#006E00"/>
</shape>

6、Button 更多

Button 更多