int Height = Math.min(1,2)
时间: 2024-04-11 19:26:11 浏览: 12
在您提供的代码中,您尝试使用 `Math.min()` 方法来获取两个整数中的最小值。然而,您的代码中存在一个语法错误,导致代码无法通过编译。
问题在于您在 `Math.min()` 方法的参数中使用了半角逗号(`,`)而不是全角逗号(`,`)。在 Java 中,应该使用全角逗号作为参数的分隔符。
正确的代码应该是:
```java
int height = Math.min(1, 2);
```
这样,`Math.min()` 方法将会返回两个整数中的最小值,即 `1`。然后,这个最小值将被赋值给变量 `height`。
相关问题
import QtQuick 2.4 import QtQuick.Controls 2.5 import QtQuick.Window 2.3 ApplicationWindow { visible: true width: 800 height: 600 title: "Drawing Board Example" property var rectStartPos: null property var rectEndPos: null property var rects: [] Item { width: 700 height: 500 property int gridSize: 20 property int scaleFactor: 100 Canvas { id: canvas anchors.fill: parent onPaint: { var ctx = getContext("2d"); var width = canvas.width; var height = canvas.height; // 清除画布 ctx.clearRect(0, 0, width, height); // 绘制网格线 ctx.lineWidth = 0.002 * parent.scaleFactor; ctx.strokeStyle = "black"; for (var x = 0; x <= width; x += parent.gridSize) { ctx.beginPath(); ctx.moveTo(x, 0); ctx.lineTo(x, height); ctx.stroke(); } for (var y = 0; y <= height; y += parent.gridSize) { ctx.beginPath(); ctx.moveTo(0, y); ctx.lineTo(width, y); ctx.stroke(); } // 绘制保存的矩形 function drawRect(x, y, width, height) { var ctx = canvas.getContext("2d"); ctx.strokeStyle = "red"; ctx.strokeRect(x, y, width, height); } for (var i = 0; i < rects.length; i++) { var rect = rects[i]; drawRect(rect.x, rect.y, rect.width, rect.height); } // 绘制正在绘制的矩形 if (rectStartPos !== null && rectEndPos !== null) { var x = Math.min(rectStartPos.x, rectEndPos.x); var y = Math.min(rectStartPos.y, rectEndPos.y); var width = Math.abs(rectStartPos.x - rectEndPos.x); var height = Math.abs(rectStartPos.y - rectEndPos.y); drawRect(x, y, width, height); } } } MouseArea { anchors.fill: parent onWheel: { parent.scaleFactor += wheel.angleDelta.y / 120; parent.scaleFactor = Math.max(parent.scaleFactor, 10); parent.gridSize = parent.scaleFactor / 5; canvas.width = width * parent.scaleFactor / 100; canvas.height = height * parent.scaleFactor / 100; canvas.requestPaint(); } onPressed: { rectStartPos = mapToItem(canvas, mouse.x, mouse.y); } onReleased: { if (rectStartPos !== null && rectEndPos !== null) { var x = Math.min(rectStartPos.x, rectEndPos.x); var y = Math.min(rectStartPos.y, rectEndPos.y); var width = Math.abs(rectStartPos.x - rectEndPos.x); var height = Math.abs(rectStartPos.y - rectEndPos.y); rects.push({x: x, y: y, width: width, height: height}); canvas.requestPaint(); } rectStartPos = null; rectEndPos = null; } onPositionChanged: { if (rectStartPos !== null) { rectEndPos = mapToItem(canvas, mouse.x, mouse.y); canvas.requestPaint(); } } } Button { id: rectButton text: "Draw Rectangle" anchors.bottom: parent.bottom anchors.horizontalCenter: parent.horizontalCenter onClicked: { console.log("Button clicked"); } } } }我希望将当前的button按钮做成一个开关控制,当按下这个开关后,绘制矩形的能力才能够触发,再次按下则失去绘制矩形的能力,
你可以在Button的onClicked事件中添加一个变量来表示当前是否可以绘制矩形,再根据这个变量来判断是否绘制矩形。代码如下:
```
import QtQuick 2.4
import QtQuick.Controls 2.5
import QtQuick.Window 2.3
ApplicationWindow {
visible: true
width: 800
height: 600
title: "Drawing Board Example"
property var rectStartPos: null
property var rectEndPos: null
property var rects: []
property bool drawRect: false
Item {
width: 700
height: 500
property int gridSize: 20
property int scaleFactor: 100
Canvas {
id: canvas
anchors.fill: parent
onPaint: {
var ctx = getContext("2d");
var width = canvas.width;
var height = canvas.height;
// 清除画布
ctx.clearRect(0, 0, width, height);
// 绘制网格线
ctx.lineWidth = 0.002 * parent.scaleFactor;
ctx.strokeStyle = "black";
for (var x = 0; x <= width; x += parent.gridSize) {
ctx.beginPath();
ctx.moveTo(x, 0);
ctx.lineTo(x, height);
ctx.stroke();
}
for (var y = 0; y <= height; y += parent.gridSize) {
ctx.beginPath();
ctx.moveTo(0, y);
ctx.lineTo(width, y);
ctx.stroke();
}
// 绘制保存的矩形
function drawRect(x, y, width, height) {
var ctx = canvas.getContext("2d");
ctx.strokeStyle = "red";
ctx.strokeRect(x, y, width, height);
}
for (var i = 0; i < rects.length; i++) {
var rect = rects[i];
drawRect(rect.x, rect.y, rect.width, rect.height);
}
// 绘制正在绘制的矩形
if (drawRect && rectStartPos !== null && rectEndPos !== null) {
var x = Math.min(rectStartPos.x, rectEndPos.x);
var y = Math.min(rectStartPos.y, rectEndPos.y);
var width = Math.abs(rectStartPos.x - rectEndPos.x);
var height = Math.abs(rectStartPos.y - rectEndPos.y);
drawRect(x, y, width, height);
}
}
}
MouseArea {
anchors.fill: parent
onWheel: {
parent.scaleFactor += wheel.angleDelta.y / 120;
parent.scaleFactor = Math.max(parent.scaleFactor, 10);
parent.gridSize = parent.scaleFactor / 5;
canvas.width = width * parent.scaleFactor / 100;
canvas.height = height * parent.scaleFactor / 100;
canvas.requestPaint();
}
onPressed: {
if (drawRect) {
rectStartPos = mapToItem(canvas, mouse.x, mouse.y);
}
}
onReleased: {
if (drawRect && rectStartPos !== null && rectEndPos !== null) {
var x = Math.min(rectStartPos.x, rectEndPos.x);
var y = Math.min(rectStartPos.y, rectEndPos.y);
var width = Math.abs(rectStartPos.x - rectEndPos.x);
var height = Math.abs(rectStartPos.y - rectEndPos.y);
rects.push({x: x, y: y, width: width, height: height});
canvas.requestPaint();
}
rectStartPos = null;
rectEndPos = null;
}
onPositionChanged: {
if (drawRect && rectStartPos !== null) {
rectEndPos = mapToItem(canvas, mouse.x, mouse.y);
canvas.requestPaint();
}
}
}
Button {
id: rectButton
text: drawRect ? "Stop Drawing" : "Start Drawing"
anchors.bottom: parent.bottom
anchors.horizontalCenter: parent.horizontalCenter
onClicked: {
drawRect = !drawRect;
if (drawRect) {
rectButton.text = "Stop Drawing";
} else {
rectButton.text = "Start Drawing";
}
}
}
}
}
```
var point = pictureBox1.PointToClient(new Point(e.X, e.Y)); string itemName = (string)e.Data.GetData(DataFormats.Text); ListViewItem item = listView1.FindItemWithText(itemName); if (item != null) { long fileSize = new FileInfo(itemName).Length; int width = Math.Min(pictureBox1.Width, Math.Max(10, (int)(fileSize / 1024))); int height = Math.Min(pictureBox1.Height, Math.Max(10, (int)(fileSize / 1024))); Bitmap bmp = new Bitmap(width, height); using (Graphics g = Graphics.FromImage(bmp)) { g.Clear(Color.White); g.DrawString(itemName, new Font("Arial", 10), Brushes.Black, new RectangleF(0, 0, width, height), new StringFormat { Alignment = StringAlignment.Center }); } point.X = Math.Min(point.X - width / 2, pictureBox1.Width - width); point.Y = Math.Min(point.Y - height / 2, pictureBox1.Height - height); point.X = Math.Max(point.X, 0); point.Y = Math.Max(point.Y, 0); pictureBox1.BackgroundImage = bmp; pictureBox1.Location = point; }什么意思
这段代码主要是在通过鼠标拖动ListView中的项到PictureBox控件上时,根据所选项的文件大小创建一个位图,并在位图上绘制文件名,然后将位图作为PictureBox的背景图,并根据鼠标位置调整PictureBox的位置。具体实现过程如下:
- 使用PointToClient()方法将鼠标位置转换为PictureBox中的相对位置;
- 获取拖动项的文本内容,即文件名;
- 通过ListView.FindItemWithText()方法查找该文件名对应的ListViewItem对象;
- 若找到对应项,则根据文件大小计算出位图的宽度和高度,并创建一个空白的位图对象;
- 在位图上绘制文件名,然后根据鼠标位置调整位图的位置;
- 将位图作为PictureBox的背景图,并将PictureBox的位置设置为调整后的位置。