java - 没有 AsyncTask 的 ProgressBar

问题描述

我想显示进度条，生成计算，然后在我这样做之后，我希望进度条消失，并且我想将 textview 设置为我的生成结果的结果。然而，当我执行以下操作时，进度条永远不会显示，但 textview 会适当更新。我最初想使用 AsyncTask 来做到这一点，但由于那已被弃用，我想尝试一种现代方法，但恐怕我无法让它工作。任何人都可以看到有什么问题吗？

genResult.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        runOnUiThread(new Runnable() {
                            public void run() {
                                // do onPreExecute stuff
                                pb.setVisibility(View.VISIBLE);
                            }
                        });
                        // do your stuff
                        boolean res = exp.genResult();
                        long startTime = System.nanoTime();
                        while(System.nanoTime()-startTime<50000){
                        }
                        result.outcomes.add(res);
                        runOnUiThread(new Runnable() {
                            public void run() {
                                // do onPostExecute stuff
                                pb.setVisibility(View.INVISIBLE);
                                lastRes.setText(Boolean.toString(res));


                            }
                        });
                    }
                }).start();
            }
        });

下面是 XML 文件

<?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">

    <Button
        android:id="@+id/gen_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="generate result"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.941" />

    <TextView
        android:id="@+id/title_bin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Title"
        app:layout_constraintBottom_toTopOf="@+id/gen_button"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.153" />

    <Button
        android:id="@+id/detail_bin_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="View Details"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.941"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.005" />

    <Button
        android:id="@+id/backbutton_bin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="4dp"
        android:text="go back"
        app:layout_constraintEnd_toStartOf="@+id/detail_bin_button"
        app:layout_constraintHorizontal_bias="0.105"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/lastresultbin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="36dp"
        android:layout_marginLeft="36dp"
        android:text="lastresult"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/backbutton_bin"
        app:layout_constraintVertical_bias="0.313" />

    <TextView
        android:id="@+id/probabilityViewer"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="208dp"
        android:text="Probability"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.65"
        app:layout_constraintStart_toEndOf="@+id/lastresultbin"
        app:layout_constraintTop_toBottomOf="@+id/detail_bin_button" />

    <TextView
        android:id="@+id/plaintext_lastres_bin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="24dp"
        android:text="Last Result"
        app:layout_constraintBottom_toTopOf="@+id/lastresultbin"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.105"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/backbutton_bin"
        app:layout_constraintVertical_bias="1.0" />

    <TextView
        android:id="@+id/plaintext_prob"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="164dp"
        android:layout_marginEnd="44dp"
        android:layout_marginRight="44dp"
        android:text="Probability of Success"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/detail_bin_button" />

    <ProgressBar
        android:id="@+id/progressBar1"
        android:layout_width="100dp"
        android:layout_height="20dp"
        android:layout_centerInParent="true"
        android:layout_marginTop="148dp"
        android:indeterminate="true"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.333"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

标签： javaandroidmultithreadingrunnable

java - 没有 AsyncTask 的 ProgressBar

问题描述

解决方案

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