Android Studio 上的模糊背景

Question

我正在开发一个需要登录页面的项目

所以在登录页面我要求android studio中的背景是模糊的。

我只希望背景模糊，而不是布局的其他元素。

我尝试了

android:alpha="0.5"

但没有成功。我怎样才能实现它

这是 xml 代码..

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:background="@drawable/gradient_bg"  //this is the background i want it to be blur
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:fontFamily="@font/roboto_black"
        android:shadowColor="#252525"
        android:text="Login"
        android:textAlignment="center"
        android:textColor="#FFFFFF"
        android:textSize="40sp"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/imageView3" />


    <EditText
        android:id="@+id/editTextText"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:ems="10"
        android:hint="Username"
        android:inputType="text"
        android:padding="18sp"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#a9a7a7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:ems="10"
        android:hint="Email Here"
        android:inputType="textEmailAddress"
        android:padding="18dp"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#A9A7A7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editTextText" />

    <ImageView
        android:id="@+id/imageView3"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_marginTop="60dp"
        android:background="@drawable/circle_bg"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.497"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/account_login" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:hint="Password"
        android:inputType="textPassword"
        android:padding="18dp"
        android:password="true"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#A9A7A7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:alpha="0.80"
        android:backgroundTint="#FFFFFF"
        android:text="Submit"
        android:textColor="@color/black"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText2" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:text="Login Using Google:"
        android:textColor="@color/white"
        android:textSize="16sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="108dp"
        android:layout_height="78dp"
        android:layout_marginTop="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView2"
        app:srcCompat="@drawable/g_logo" />

</androidx.constraintlayout.widget.ConstraintLayout>

我尝试包括

android:alpha="0.5"

但没有成功。

希望能找到解决方案。

Answer 1

当您将背景图像设置为根视图并设置 alpha 时，这就是根视图内的其他元素也会变得模糊的原因。

您可以使用根视图的模糊图像作为背景。

或

您可以为背景图像添加图像视图，如下所示

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    tools:context=".MainActivity">

<!--Use this imageview as background-->
<androidx.appcompat.widget.AppCompatImageView
        android:layout_width="match_parent"
        android:alpha="0.5  // you can set the image opacity by changing this
        android:scaleType="centerCrop"    // you can set scaleType as you want
        app:srcCompat="@drawable/gradient_bg"//this is the background you want it to be blur
        android:layout_height="match_parent"/>

    <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:fontFamily="@font/roboto_black"
        android:shadowColor="#252525"
        android:text="Login"
        android:textAlignment="center"
        android:textColor="#FFFFFF"
        android:textSize="40sp"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/imageView3" />


    <EditText
        android:id="@+id/editTextText"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:ems="10"
        android:hint="Username"
        android:inputType="text"
        android:padding="18sp"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#a9a7a7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:ems="10"
        android:hint="Email Here"
        android:inputType="textEmailAddress"
        android:padding="18dp"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#A9A7A7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editTextText" />

    <ImageView
        android:id="@+id/imageView3"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_marginTop="60dp"
        android:background="@drawable/circle_bg"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.497"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/account_login" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="250dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:background="@drawable/roudedshape"
        android:hint="Password"
        android:inputType="textPassword"
        android:padding="18dp"
        android:password="true"
        android:textAlignment="center"
        android:textColor="@color/white"
        android:textColorHint="#A9A7A7"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.496"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:alpha="0.80"
        android:backgroundTint="#FFFFFF"
        android:text="Submit"
        android:textColor="@color/black"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText2" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:text="Login Using Google:"
        android:textColor="@color/white"
        android:textSize="16sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="108dp"
        android:layout_height="78dp"
        android:layout_marginTop="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView2"
        app:srcCompat="@drawable/g_logo" />

</androidx.constraintlayout.widget.ConstraintLayout>