我遇到了一个问题，实施Daniel Shiffman将example拖入我的草图中。我以前使用它并且它很棒，但是我试图使用它有一些“花哨”的循环来将它应用于多个对象（在这种情况下是文本）但无济于事。除了对象不应该拖动时，一切都正常工作。从逻辑上讲，这是因为Line类中的offsetX和offsetY属性会继续更新，从而迫使对象保持静止。我确信有一个解决方案，但我无法弄清楚。也许我已经盯着它看了太久。我非常感谢你的帮助！
String[] doc; //array of Strings from each text documents line
int tSize; //text size
float easing; //easing
int boundaryOverlap; //value for words to overlap edges by
PFont font; //font
Lines lines;
boolean clicked = false;
void setup(){
size(displayWidth/2,displayHeight);
background(255);
fill(0);
boundaryOverlap = 20; //value for words to overlap edges by
tSize = 32; //text size
//loads and formats text
doc = loadStrings("text.txt");
font = loadFont("Times-Roman-48.vlw");
textFont(font, tSize);
//lines object
lines = new Lines(doc);
//populate xAddition and yAddition arrays
lines.populateArrays();
}
void draw(){
background(255);
fill(0);
//loops through each line in .txt
for(int i = 0; i <= doc.length-1; i++){
if(clicked) lines.clicked(i);
lines.move(i, clicked); //update doc[i] positions //deletes
lines.display(i); //draws text for each line of text in text.txt
}
}
void mousePressed(){
clicked = true;
}
void mouseReleased(){
clicked = false;
lines.dragging = false;
}
这是行类：
class Lines{
//class properties
float[] x; //array holding random values to be added to x for placement
float[] y; //array holding random values to be added to y for placement
float offsetX;
float offsetY;
String[] doc;
boolean dragging = false; //boolean for dragging
//construct
Lines(String[] tempDoc){
doc = tempDoc;
}
//fills x and y arrays
void populateArrays(){
x = new float[doc.length];
y = new float[doc.length];
//populates x and y arrays
for(int i = 0; i <= doc.length-1; i++){
x[i] = int(random(0-boundaryOverlap, width-boundaryOverlap));
y[i] = int(random(0, height-boundaryOverlap));
}
}
//draws text
void display(int i){
text(doc[i], x[i], y[i]); //draw text
//if(addition[i] != null) text(addition[i], x[i], y[i]+20);
}
void clicked(int i){
if(mouseX > x[i] &&
mouseX < x[i]+textWidth(doc[i]) &&
mouseY < y[i] &&
mouseY > y[i]-tSize){
dragging = true;
offsetX = x[i] - mouseX;
offsetY = y[i] - mouseY;
}
}
//updates text positions
void move(int i, boolean clicked){
//if mouseOver text hover gray
if( mouseX > x[i] &&
mouseX < x[i]+textWidth(doc[i]) &&
mouseY < y[i] &&
mouseY > y[i]-tSize){
fill(100); //gray text fill
if(dragging){
x[i] = mouseX + offsetX;
y[i] = mouseY + offsetY;
}
}
else{
fill(0); //if not text not mouseOver fill is black
dragging = false;
}
}
//delete
void delete(int i){
//if "delete" is pressed
if (keyPressed){
if(key == 8){
doc[i] = ""; // doc[line String that is being hovered over] is replaced with null
keyCode = 1;
}
}
}
}
答案 0 :(得分：1)
首先，请勿使用vlw字体。当每个人都安装了Times New Roman时，没有理由使用位图图像文件。只需使用createFont（“Times New Roman”，48）。现在你甚至可以改变文本大小而不会看起来很糟糕，因为你只是加载了字体而不是位图图像。
那就是说，这段代码并不是那么好......但是使用它，问题出在这里：
for(int i = 0; i <= doc.length-1; i++){
if(clicked) lines.clicked(i);
lines.move(i, clicked); //update doc[i] positions //deletes
lines.display(i); //draws text for each line of text in text.txt
}
您检查是否已点击，如果是，请将该行标记为已点击。然后你完全忽略它并移动所有的行，而不看“点击”状态（它根本不用于移动功能）。
那就是说，你要做的事情可以做得更好，更清洁：
LineCollection lines;
float textSize;
void setup(){
size(400,400);
// fix the text size, reference a real font
textSize = 32;
textFont(createFont("Times New Roman", textSize));
// parse strings, construct Lines container
String[] textValues = new String[]{"lol","cat"};
lines = new LineCollection(textValues);
// Do not loop! only update when events warrant,
// based on redraw() calls
noLoop();
}
// fall through drawing
void draw() { background(255); lines.draw(); }
// fall through event handling
void mouseMoved() { lines.mouseMoved(mouseX,mouseY); redraw(); }
void mousePressed() { lines.mousePressed(mouseX,mouseY); redraw(); }
void mouseDragged() { lines.mouseDragged(mouseX,mouseY); redraw(); }
void mouseReleased() { lines.mouseReleased(mouseX,mouseY); redraw(); }
/**
* A collection of lines. This is *only* a collecton,
* it is simply responsible for passing along events.
*/
class LineCollection {
Line[] lines;
int boundaryOverlap = 20;
// construct
LineCollection(String[] strings){
lines = new Line[strings.length];
int x, y;
for(int i=0, last=strings.length; i<last; i++) {
x = (int) random(0, width);
y = (int) random(0, height);
lines[i] = new Line(strings[i], x, y);
}
}
// fall through drawing
void draw() {
// since we don't care about counting elements
// in our "lines" container, we use the "foreach"
// version of the for loop. This is identical to
// "for(int i=0; i<lines.size(); i++) {
// Line l = lines[i];
// [... use l here ...]
// }"
// except we don't have to unpack our list manually.
for(Line l: lines) { l.draw(); }
}
// fall through event handling
void mouseMoved(int mx, int my) { for(Line l: lines) { l.mouseMoved(mx,my); }}
void mousePressed(int mx, int my) { for(Line l: lines) { l.mousePressed(mx,my); }}
void mouseDragged(int mx, int my) { for(Line l: lines) { l.mouseDragged(mx,my); }}
void mouseReleased(int mx, int my) { for(Line l: lines) { l.mouseReleased(mx,my); }}
}
/**
* Individual lines
*/
class Line {
String s;
float x, y, w, h;
boolean active;
color fillColor = 0;
int cx, cy, ox=0, oy=0;
public Line(String _s, int _x, int _y) {
s = _s;
x = _x;
y = _y;
w = textWidth(s);
h = textSize;
}
void draw() {
fill(fillColor);
text(s,ox+x,oy+y+h);
}
boolean over(int mx, int my) {
return (x <= mx && mx <= x+w && y <= my && my <= y+h);
}
// Mouse moved: is the cursor over this line?
// if so, change the fill color
void mouseMoved(int mx, int my) {
active = over(mx,my);
fillColor = (active ? color(155,155,0) : 0);
}
// Mouse pressed: are we active? then
// mark where we started clicking, so
// we can do offset computation on
// mouse dragging.
void mousePressed(int mx, int my) {
if(active) {
cx = mx;
cy = my;
ox = 0;
oy = 0;
}
}
// Mouse click-dragged: if we're active,
// change the draw offset, based on the
// distance between where we initially
// clicked, and where the mouse is now.
void mouseDragged(int mx, int my) {
if(active) {
ox = mx-cx;
oy = my-cy;
}
}
// Mouse released: if we're active,
// commit the offset to this line's
// position. Also, regardless of
// whether we're active, now we're not.
void mouseReleased(int mx, int my) {
if(active) {
x += mx-cx;
y += my-cy;
ox = 0;
oy = 0;
}
active = false;
}
}
<强>更新
解释此代码中使用的“for”的foreach版本。