读取文本文件并将其一行一行地添加到多个textview中，而不是一次

Question

我编写了一个程序，读取文本文件，检查第一个元素是否为1，并将其显示给textview(TextViewDisk1)，并检查其是否为2，等等。它确实很有效，但只适用于第一行。在程序读取下一行后，应用程序停止。

logcat

android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views .

如何解决这个问题?

代码

 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //Read text file and show number on the textview
    new Thread(new Runnable() {
        @Override
        public void run() {
            final TextView TextDisk1 = (TextView) findViewById(R.id.TextDisk1);
            final TextView TextDisk2 = (TextView) findViewById(R.id.TextDisk2);
            final TextView TextDisk3 = (TextView) findViewById(R.id.TextDisk3);
            final TextView TextDisk4 = (TextView) findViewById(R.id.TextDisk4);
            final TextView TextDisk5 = (TextView) findViewById(R.id.TextDisk5);
                try {
                    InputStream stream = getAssets().open("Messwerte.txt");
                    InputStreamReader reader = new InputStreamReader(stream);
                    BufferedReader buffer = new BufferedReader(reader);
                    String lines;
                    for (int i = 0; i < 2400; i++) {
                        lines = buffer.readLine();
                        String[] line = lines.split("t");
                        String first = line[0];
                        String second = line[1];
                        String third = line[2];
                        TextDisk3.setText(third);
                        if(first.equals("1"))
                        {
                            TextDisk1.setText(second);
                        }
                        else if(first.equals("2"))
                        {
                            TextDisk2.setText(second);
                        }
                        else if(first.equals("4"))
                        {
                            TextDisk4.setText(second);
                        }
                        else if(first.equals("5"))
                        {
                            TextDisk5.setText(second);
                        }
                        i++;
                        Thread.sleep(6000);
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
        }
    }).start();

Answer 1

如果你想从一个线程，不是ui线程修改textview你需要使用runOnuiThread(..)。下面是一个例子。

new Thread(new Runnable() {
            @Override
            public void run() {
                final TextView TextDisk1 = (TextView) findViewById(R.id.TextDisk1);
                final TextView TextDisk2 = (TextView) findViewById(R.id.TextDisk2);
                final TextView TextDisk3 = (TextView) findViewById(R.id.TextDisk3);
                final TextView TextDisk4 = (TextView) findViewById(R.id.TextDisk4);
                final TextView TextDisk5 = (TextView) findViewById(R.id.TextDisk5);
                try {
                    InputStream stream = getAssets().open("Messwerte.txt");
                    InputStreamReader reader = new InputStreamReader(stream);
                    BufferedReader buffer = new BufferedReader(reader);
                    String lines;
                    for (int i = 0; i < 2400; i++) {
                        lines = buffer.readLine();
                        String[] line = lines.split("t");
                        String first = line[0];
                        String second = line[1];
                        String third = line[2];
                        WriteText(TextDisk3, third);
                        if (first.equals("1")) {
                            WriteText(TextDisk1, second);
                        }
                        else if (first.equals("2")) {
                            WriteText(TextDisk2, second);
                        } else if (first.equals("4")) {
                            WriteText(TextDisk4, second);
                        }
                        else if (first.equals("5")) {
                            WriteText(TextDisk5, second);
                        }
                        i++;
                        Thread.sleep(6000);
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }
    public void WriteText(final TextView textview, final String value) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                textview.setText(value);
            }
        });
    }
}

如果你的文件不是2400行，它将抛出一个nullPointerException