Question

我在经过测试的项目page中创建了一个非常简单的Bottom Sheet。首先，我创建了布局：

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/mainContent"
    android:fitsSystemWindows="true"
    tools:context=".MainActivity">

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"
            android:paddingTop="24dp">

            <Button
                android:id="@+id/btn_1"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Button 1"
                android:padding="16dp"
                android:layout_margin="8dp"
                android:textColor="@android:color/white"
                android:background="@android:color/holo_green_dark"/>
        </LinearLayout>

    </ScrollView>

    <android.support.v4.widget.NestedScrollView
        android:id="@+id/bottom_sheet"
        android:layout_width="match_parent"
        android:layout_height="350dp"
        android:clipToPadding="true"
        android:background="@android:color/holo_orange_light"
        app:layout_behavior="android.support.design.widget.BottomSheetBehavior">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:text="Bottom Sheets"
            android:paddingTop="16dp"
            android:textSize="16sp"/>

    </android.support.v4.widget.NestedScrollView>

</android.support.design.widget.CoordinatorLayout>

在MainActivity中，我编写了以下代码：

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private BottomSheetBehavior mBottomSheetBehavior;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        View bottomSheet = findViewById(R.id.bottom_sheet);

        Button btn1 = findViewById(R.id.btn_1);
        btn1.setOnClickListener(this);

        mBottomSheetBehavior = BottomSheetBehavior.from(bottomSheet);
        mBottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN);

    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_1:
                mBottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
                break;
        }
    }
}

但是当我在仿真器BottomSheetBehavior上运行应用程序时，是EXPANDED ！！！当我将代码更改为此时：

switch (view.getId()) {
    case R.id.btn_1:
        mBottomSheetBehavior.setState(BottomSheetBehavior.STATE_COLLAPSED);
        break;

然后按btn_1 BottomSheetBehavior不会折叠？问题是什么？这是我的礼物：

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:28.0.0-alpha3'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.1'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
    implementation 'com.android.support:design:28.0.0-alpha3'
}

Answer 1

您必须将这两行添加到底部工作表布局文件中

app:behavior_peekHeight="0dp"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior"

layout_behavior-将底部工作表折叠和展开行为应用于上下布局 peekHeight-活动启动时要初始显示的布局高度，您可以根据视图高度进行更改

如果已经添加了它，那么可以请您共享包含底部工作表布局的主活动xml文件

底页未展开或折叠

1 个答案: